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Wang S, Kawashima N, Han P, Sunada-Nara K, Yu Z, Tazawa K, Fujii M, Kieu TQ, Okiji T. MicroRNA-27a-5p Downregulates Expression of Proinflammatory Cytokines in Lipopolysaccharide-Stimulated Human Dental Pulp Cells via the NF-κB Signaling Pathway. Int J Mol Sci 2024; 25:9694. [PMID: 39273640 PMCID: PMC11395329 DOI: 10.3390/ijms25179694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2024] [Revised: 09/05/2024] [Accepted: 09/05/2024] [Indexed: 09/15/2024] Open
Abstract
MicroRNA-27a-5p (miR-27a-5p) was significantly upregulated in dental pulp inflammation, yet its underlying mechanisms remain unclear. This study investigated the effect of miR-27a-5p on the expression of proinflammatory cytokines in human dental pulp cells (hDPCs) stimulated by lipopolysaccharide (LPS). LPS-stimulated hDPCs showed concurrent increases in the expression of miR-27a-5p and proinflammatory cytokines (IL-6, IL-8, and MCP1), and the increased expression was suppressed by NF-κB inhibitor BAY 11-0785. Transfection of the miR-27a-5p mimic downregulated the expression of proinflammatory cytokines, NF-κB activity, and the expression of NF-κB signaling activators (TAB1, IRAK4, RELA, and FSTL1) in LPS-stimulated hDPCs. Luciferase reporter assays revealed that miR-27a-5p bound directly to the 3'-UTR of TAB1. siTAB1 downregulated NF-κB activity and proinflammatory cytokine expression. Downregulation of proinflammatory cytokine expression, NF-κB activity, and NF-κB signaling activator expression (TAB1, IRAK4, and RELA) was also found in LPS-stimulated rat incisor pulp tissue explants following transfection with the miR-27a-5p mimic ex vivo. MiR-27a-5p, whose expression was induced by NF-κB signaling, negatively regulated the synthesis of proinflammatory cytokines via targeting NF-κB signaling. In particular, TAB1, a potent NF-κB activator, was targeted by miR-27a-5p. These results provide insights into the negative regulatory effects of miR-27a-5p, particularly those targeting the TAB1-NF-κB signaling pathway, on pulp inflammation.
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Affiliation(s)
- Shihan Wang
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Nobuyuki Kawashima
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Peifeng Han
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Keisuke Sunada-Nara
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Ziniu Yu
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Kento Tazawa
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Mayuko Fujii
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
| | - Thoai Quoc Kieu
- Department of Pediatric Dentistry, Faculty of Odonto-Stomatology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City 17000, Vietnam
| | - Takashi Okiji
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo 113-8549, Japan
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Bhat R, Shetty S, Rai P, Kumar BK, Shetty P. Revolutionizing the diagnosis of irreversible pulpitis - Current strategies and future directions. J Oral Biosci 2024; 66:272-280. [PMID: 38508491 DOI: 10.1016/j.job.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND Pulpitis primarily arises from the pulp space infection by oral microbiota. Vital pulp therapy is a minimally invasive approach that relies on assessing the severity of pulpal inflammation to facilitate repair. However, the current evaluation methods prescribed by the American Association of Endodontics are subjective, leading to ambiguity in assessment. Therefore, this review aims to explore molecular strategies for evaluating the severity of pulpal inflammation to accurately predict the success of pulp vitality preservation in clinical settings. METHODOLOGY This review was conducted by searching relevant keywords, such as irreversible pulpitis, pulpitis biomarkers, molecular diagnosis, inflammation, and genomic strategies, in databases such as PubMed, Web of Science, and Scopus to address the subjective nature of diagnosis. The data included in this review were collected up to April 2023. The literature search revealed well-documented limitations in clinically assessing the pulp inflammatory. Molecular approaches that aid in clinical differentiation between irreversible and reversible pulpitis may potentially enhance favorable outcomes in vital pulp therapy. Non-invasive diagnostic methods for pulpal assessment would also be valuable for determining whether the inflamed pulp is reversible, irreversible, or necrotic. CONCLUSION The present review examines the various molecular diagnostic approaches that have revolutionized the medical field and are considered the most promising empirical methodologies for the proactive detection of pulpal diseases. It also provides comprehensive insights into the current diagnostic methods, associated challenges, next-generation strategies, and future directions for diagnosing the severity of pulp inflammation.
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Affiliation(s)
- Raksha Bhat
- Nitte (Deemed to be University), Department of Conservative Dentistry & Endodontics, AB Shetty Memorial Institute of Dental Sciences (ABSMIDS), Mangalore, 575018, Karnataka, India.
| | - Shishir Shetty
- Nitte (Deemed to be University), Department of Conservative Dentistry & Endodontics, AB Shetty Memorial Institute of Dental Sciences (ABSMIDS), Mangalore, 575018, Karnataka, India.
| | - Praveen Rai
- Nitte (Deemed to be University), Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research (NUCSER), Mangalore, 575018, Karnataka, India.
| | - Ballamoole Krishna Kumar
- Nitte (Deemed to be University), Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research (NUCSER), Mangalore, 575018, Karnataka, India.
| | - Preethesh Shetty
- Nitte (Deemed to be University), Department of Conservative Dentistry & Endodontics, AB Shetty Memorial Institute of Dental Sciences (ABSMIDS), Mangalore, 575018, Karnataka, India.
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Sobieszczański J, Mertowski S, Sarna-Boś K, Stachurski P, Grywalska E, Chałas R. Root Canal Infection and Its Impact on the Oral Cavity Microenvironment in the Context of Immune System Disorders in Selected Diseases: A Narrative Review. J Clin Med 2023; 12:4102. [PMID: 37373794 DOI: 10.3390/jcm12124102] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/09/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
The oral cavity has a specific microenvironment, and structures such as teeth are constantly exposed to chemical and biological factors. Although the structure of the teeth is permanent, due to exposure of the pulp and root canal system, trauma can have severe consequences and cause the development of local inflammation caused by external and opportunistic pathogens. Long-term inflammation can affect not only the local pulp and periodontal tissues but also the functioning of the immune system, which can trigger a systemic reaction. This literature review presents the current knowledge on root canal infections and their impact on the oral microenvironment in the context of immune system disorders in selected diseases. The result of the analysis of the literature is the statement that periodontal-disease-caused inflammation in the oral cavity may affect the development and progression of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, or Sjogren's syndrome, as well as affecting the faster progression of conditions in which inflammation occurs such as, among others, chronic kidney disease or inflammatory bowel disease.
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Affiliation(s)
- Jarosław Sobieszczański
- Preclinical Dentistry Lab, Medical University of Lublin, Chodźki 6 Street, 20-093 Lublin, Poland
| | - Sebastian Mertowski
- Department of Experimental Immunology, Medical University of Lublin, 4a Chodźki Street, 20-093 Lublin, Poland
| | - Katarzyna Sarna-Boś
- Department of Dental Prosthetics, Medical University of Lublin, Chodźki 6 Street, 20-093 Lublin, Poland
| | - Piotr Stachurski
- Department of Pediatric Dentistry, Medical University of Lublin, 20-093 Lublin, Poland
| | - Ewelina Grywalska
- Department of Experimental Immunology, Medical University of Lublin, 4a Chodźki Street, 20-093 Lublin, Poland
| | - Renata Chałas
- Department of Oral Medicine, Medical University of Lublin, Chodźki 6 Street, 20-093 Lublin, Poland
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Hasan A, Roome T, Wahid M, Ansari SA, Akhtar H, Jilani SNA, Kiyani A. Gene expression analysis of toll like receptor 2 and 4, Dectin-1, Osteopontin and inflammatory cytokines in human dental pulp ex-vivo. BMC Oral Health 2022; 22:563. [PMID: 36463168 PMCID: PMC9719632 DOI: 10.1186/s12903-022-02621-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 11/25/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Toll like receptors (TLR) 2 and 4 present on innate immune cells of the dental pulp detect cariogenic bacteria. Along with bacteria, C. albicans may also be present in dental caries. The presence of C. albicans can be detected by Dectin-1 a C type Lectin receptor. Expression of Dectin-1 in human pulpits has not been reported. Similarly, cytokines are released as a consequence of dental pulp inflammation caused by cariogenic bacteria. The T helper (Th) 1 inflammatory response leads to exacerbation of inflammation and its relationship with Osteopontin (OPN) is not known in pulp inflammation. OBJECTIVE The aim of this study was to observe the expression of Dectin-1, TLR-2, OPN and pro-inflammatory cytokines in irreversibly inflamed human dental pulp and to observe relationship between Dectin-1/TLR-2 and OPN/Pro-inflammatory cytokines in the presence of appropriate controls. METHODS A total of 28 subjects diagnosed with irreversible pulpitis were included in this ex-vivo study. Fifteen samples were subjected to standard hematoxylin and Eosin (H&E) and immunohistochemistry staining. Whereas, gene expression analysis was performed on 13 samples to observe mRNA expression of pro-inflammatory cytokines; tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (ß), IL-6 Dectin-1, OPN, TLR-2 and TLR-4. SPSS version 21 was used for statistical analysis. One way analysis of variance (ANOVA), Pearson correlation and Chi-square test were used at p ≤ 0.05. RESULTS Gene expressions of Dectin-1, TLR-2 and TLR-4 were observed in all samples. Dectin-1 and TLR-2 expressions were significantly correlated (r = 0.5587, p = 0.0002). Similarly, OPN and TNF-α expression showed a significant correlation (r = 0.5860, p = 0001). The agreement between histologic and clinical diagnosis was 69.2% in the cases of irreversible pulpitis. CONCLUSION Dectin-1 was expressed by inflamed human dental pulp. Dectin-1 and TLR-2 expression pattern was suggestive of a collaborative receptor response in inflamed pulp environment. OPN and TNF-α expressions showed a positive correlation indicating a possible relationship.
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Affiliation(s)
- Arshad Hasan
- grid.412080.f0000 0000 9363 9292Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences, Baba-E-Urdu Road, Karachi, 74200 Pakistan
| | - Talat Roome
- Department of Pathology, Section Molecular Pathology, Dow International Medical College, Ojha Campus, Gulzar-E-Hijri, Karachi, Pakistan ,grid.412080.f0000 0000 9363 9292Dow Institute for Advanced Biological and Animal Research, Dow University of Health Sciences, Ojha Campus, Gulzar-E-Hijri, Karachi, Pakistan
| | - Mohsin Wahid
- grid.412080.f0000 0000 9363 9292Department of Pathology, Dow International Medical College, Dow University of Health Sciences, Ojha Campus, Gulzar-E-Hijri, Karachi, Pakistan ,grid.412080.f0000 0000 9363 9292Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Ojha Campus, Gulzar-E-Hijri, Karachi, Pakistan
| | - Shazia Akbar Ansari
- grid.412080.f0000 0000 9363 9292Department of Oral Pathology, Dow Dental College, Dow University of Health Sciences, Baba-E-Urdu Road, Karachi, 74200 Pakistan
| | - Hira Akhtar
- grid.412080.f0000 0000 9363 9292Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences, Baba-E-Urdu Road, Karachi, 74200 Pakistan
| | - Syeda Neha Ahmed Jilani
- grid.412080.f0000 0000 9363 9292Dow Institute for Advanced Biological and Animal Research, Dow University of Health Sciences, Ojha Campus, Gulzar-E-Hijri, Karachi, Pakistan
| | - Amber Kiyani
- grid.414839.30000 0001 1703 6673Department of Oral Medicine and Diagnosis, Islamic International Dental College, Riphah International University, 7th Avenue G-7/4, Islamabad, Pakistan
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5
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Altaie AM, Venkatachalam T, Samaranayake LP, Soliman SSM, Hamoudi R. Comparative Metabolomics Reveals the Microenvironment of Common T-Helper Cells and Differential Immune Cells Linked to Unique Periapical Lesions. Front Immunol 2021; 12:707267. [PMID: 34539639 PMCID: PMC8446658 DOI: 10.3389/fimmu.2021.707267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 08/12/2021] [Indexed: 12/12/2022] Open
Abstract
Periapical abscesses, radicular cysts, and periapical granulomas are the most frequently identified pathological lesions in the alveolar bone. While little is known about the initiation and progression of these conditions, the metabolic environment and the related immunological behaviors were examined for the first time to model the development of each pathological condition. Metabolites were extracted from each lesion and profiled using gas chromatography-mass spectrometry in comparison with healthy pulp tissue. The metabolites were clustered and linked to their related immune cell fractions. Clusters I and J in the periapical abscess upregulated the expression of MMP-9, IL-8, CYP4F3, and VEGF, while clusters L and M were related to lipophagy and apoptosis in radicular cyst, and cluster P in periapical granuloma, which contains L-(+)-lactic acid and ethylene glycol, was related to granuloma formation. Oleic acid, 17-octadecynoic acid, 1-nonadecene, and L-(+)-lactic acid were significantly the highest unique metabolites in healthy pulp tissue, periapical abscess, radicular cyst, and periapical granuloma, respectively. The correlated enriched metabolic pathways were identified, and the related active genes were predicted. Glutamatergic synapse (16–20),-hydroxyeicosatetraenoic acids, lipophagy, and retinoid X receptor coupled with vitamin D receptor were the most significantly enriched pathways in healthy control, abscess, cyst, and granuloma, respectively. Compared with the healthy control, significant upregulation in the gene expression of CYP4F3, VEGF, IL-8, TLR2 (P < 0.0001), and MMP-9 (P < 0.001) was found in the abscesses. While IL-12A was significantly upregulated in cysts (P < 0.01), IL-17A represents the highest significantly upregulated gene in granulomas (P < 0.0001). From the predicted active genes, CIBERSORT suggested the presence of natural killer cells, dendritic cells, pro-inflammatory M1 macrophages, and anti-inflammatory M2 macrophages in different proportions. In addition, the single nucleotide polymorphisms related to IL-10, IL-12A, and IL-17D genes were shown to be associated with periapical lesions and other oral lesions. Collectively, the unique metabolism and related immune response shape up an environment that initiates and maintains the existence and progression of these oral lesions, suggesting an important role in diagnosis and effective targeted therapy.
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Affiliation(s)
- Alaa Muayad Altaie
- Research Institute for Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates.,Department of Oral and Craniofacial Health Sciences, College of Dental Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Thenmozhi Venkatachalam
- Research Institute for Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Lakshman P Samaranayake
- Department of Oral and Craniofacial Health Sciences, College of Dental Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Oral Biosciences, Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong, SAR China
| | - Sameh S M Soliman
- Research Institute for Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates.,Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, Sharjah, United Arab Emirates
| | - Rifat Hamoudi
- Research Institute for Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Division of Surgery and Interventional Science, University College London, London, United Kingdom
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6
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Tong X, Hou S, Ma M, Zhang L, Zou R, Hou T, Niu L. The integration of transcriptome-wide association study and mRNA expression profiling data to identify candidate genes and gene sets associated with dental caries. Arch Oral Biol 2020; 118:104863. [DOI: 10.1016/j.archoralbio.2020.104863] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 07/26/2020] [Accepted: 07/28/2020] [Indexed: 12/19/2022]
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Abstract
INTRODUCTION Like many tissues, the dental pulp is equipped with innate and adaptive immune responses, designed to defend against infection and limit its spread. The pulp's innate immune response includes the synthesis and release of antimicrobial peptides by several dental pulp cell types. These naturally-occurring antimicrobial peptides have broad spectrum activity against bacteria, fungi and viruses. There is a resurgence of interest in the bioactivities of naturally-occurring antimicrobial peptides, largely driven by the need to develop alternatives to antibiotics. METHODS This narrative review focused on the general properties of antimicrobial peptides, providing an overview of their sources and actions within the dental pulp. RESULTS We summarized the relevance of antimicrobial peptides in defending the dental pulp, highlighting the potential for many of these antimicrobials to be modified or mimicked for prospective therapeutic use. CONCLUSION Antimicrobial peptides and novel peptide-based therapeutics are particularly attractive as emerging treatments for polymicrobial infections, such as endodontic infections, because of their broad activity against a range of pathogens.
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Affiliation(s)
- Fionnuala T Lundy
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland.
| | - Christopher R Irwin
- Centre for Dentistry, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland
| | - Denise F McLean
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland
| | - Gerard J Linden
- Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland
| | - Ikhlas A El Karim
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland
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8
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Jafari R, Karamzadeh R, Pesaran Hajabbas F, Sayyadizadeh F, Chekini Z, Aghajanpour S, Shakeri L, Nazarimoghaddam K, Aflatoonian R. Human closed and open apex premolar teeth express different toll-like receptor. Mol Genet Genomic Med 2020; 8:e1268. [PMID: 32400961 PMCID: PMC7336733 DOI: 10.1002/mgg3.1268] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/23/2020] [Accepted: 03/30/2020] [Indexed: 12/27/2022] Open
Abstract
Background The innate immune activation which promotes inflammation responses in the dental pulp tissue leads to the progression of dentin caries. Accordingly, toll‐like receptors (TLRs) are key molecules of the innate immune system that identify pathogen‐associated molecular patterns (PAMPs) on microorganisms and may have a critical role in a dental injury. Therefore, this study aimed to investigate the expression of TLR2, TLR3, and TLR4 in the human dental pulp of opened and closed apex teeth. Methods Human dental pulps were derived from the healthy opened and closed apex premolar, in which extraction was indicated for orthodontic reasons. The extraction of RNA was performed and the gene expression determined by real‐time polymerase chain reaction (RT‐PCR). The result from real‐time PCR was confirmed using western blot analysis. Results Real‐time PCR data analysis showed that the expression TLR2 and TLR4 were significantly increased in closed apex premolar teeth compared to open apex teeth, whereas TLR3 expression was not significantly different in these two groups (p < .05). Conclusion The results of the present study suggested increased expression of TLR2 and TLR4 by the maturation of the apex, which may be due to the presence of microorganisms in the normal or destructed dental pulp tissue. Thus, identifying the expression of TLRs molecules in dental pulp tissue helps to develop a deeper knowledge of the immune responses in the oral cavity.
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Affiliation(s)
- Reza Jafari
- School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Razieh Karamzadeh
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.,Department of Stem Cell and Development Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | | | | | - Zahra Chekini
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Samaneh Aghajanpour
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.,Anatomy Department, School of Medicine, Iran University of Medical Science, Tehran, Iran
| | - Leila Shakeri
- Faculty of Dentistry, Shahed University, Tehran, Iran
| | | | - Reza Aflatoonian
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
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9
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Kaewpitak A, Bauer CS, Seward EP, Boissonade FM, Douglas CWI. Porphyromonas gingivalis
lipopolysaccharide rapidly activates trigeminal sensory neurons and may contribute to pulpal pain. Int Endod J 2020; 53:846-858. [DOI: 10.1111/iej.13282] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 02/12/2020] [Indexed: 01/19/2023]
Affiliation(s)
- A. Kaewpitak
- School of Clinical Dentistry University of Sheffield Sheffield UK
| | - C. S. Bauer
- Department of Biomedical Science University of Sheffield Sheffield UK
| | - E. P. Seward
- Department of Biomedical Science University of Sheffield Sheffield UK
| | - F. M. Boissonade
- School of Clinical Dentistry University of Sheffield Sheffield UK
| | - C. W. I. Douglas
- School of Clinical Dentistry University of Sheffield Sheffield UK
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10
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Fawzy El-Sayed KM, Elsalawy R, Ibrahim N, Gadalla M, Albargasy H, Zahra N, Mokhtar S, El Nahhas N, El Kaliouby Y, Dörfer CE. The Dental Pulp Stem/Progenitor Cells-Mediated Inflammatory-Regenerative Axis. TISSUE ENGINEERING PART B-REVIEWS 2019; 25:445-460. [DOI: 10.1089/ten.teb.2019.0106] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Karim M. Fawzy El-Sayed
- Oral Medicine and Periodontology Department, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt
- Clinic for Conservative Dentistry and Periodontology, School of Dental Medicine, Christian Albrechts University, Kiel, Germany
| | | | | | | | | | - Nehal Zahra
- Faculty of Dentistry, New Giza University, Giza, Egypt
| | | | | | | | - Christof E. Dörfer
- Clinic for Conservative Dentistry and Periodontology, School of Dental Medicine, Christian Albrechts University, Kiel, Germany
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11
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Hwang H, Kim J, Oh S, Song JH, Yang J, Zang Y, Kim Y, Lee S, Hwang Y, Koh J. TLR5 activation induces expression of the pro‐inflammatory mediator Urokinase Plasminogen Activator via NF‐κB and MAPK signalling pathways in human dental pulp cells. Int Endod J 2019; 52:1479-1488. [DOI: 10.1111/iej.13140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 05/01/2019] [Indexed: 12/11/2022]
Affiliation(s)
- H.‐S. Hwang
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - J.‐W. Kim
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - S.‐H. Oh
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - J. H. Song
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - J.‐W. Yang
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - Y. Zang
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - Y.‐H. Kim
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
| | - S.‐E. Lee
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
| | - Y.‐C. Hwang
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
- Department of Conservative Dentistry, School of Dentistry Chonnam National University Gwangju Korea
| | - J.‐T. Koh
- Department of Pharmacology and Dental TherapeuticsChonnam National UniversityGwangju Korea
- Research Center for Biomineralization DisordersChonnam National UniversityGwangju Korea
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12
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Nara K, Kawashima N, Noda S, Fujii M, Hashimoto K, Tazawa K, Okiji T. Anti-inflammatory roles of microRNA 21 in lipopolysaccharide-stimulated human dental pulp cells. J Cell Physiol 2019; 234:21331-21341. [PMID: 31042008 DOI: 10.1002/jcp.28737] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 03/16/2019] [Accepted: 04/10/2019] [Indexed: 12/19/2022]
Abstract
microRNAs are small noncoding RNA molecules that regulate RNA silencing and posttranscriptional gene expression, and many microRNAs are involved in inflammatory processes. In particular, microRNA 21 (miR-21) is upregulated in inflammatory environment and reported to induce anti-inflammatory responses. However, the involvement of miR-21 in pulpal inflammation and the precise mechanisms of anti-inflammatory reactions induced by miR-21 remain unclear. We hypothesized that miR-21-5p expression is induced in lipopolysaccharide (LPS)-stimulated human dental pulp cells (hDPCs) and that miR-21-5p downregulates the proinflammatory cytokine expression in LPS-stimulated hDPCs. We found that miR-21-5p was upregulated in LPS-stimulated hDPCs concomitant with elevated proinflammatory cytokine expression and nuclear factor-kappa B (NF-κB) phosphorylation. miR-21-5p and cytokine expression were downregulated by BAY11-7085 and caffeic acid phenylethyl ester (CAPE), specific and potent NF-κB inhibitors. Enforced expression of miR-21-5p downregulated the Toll-like receptor (TLR)/NF-κB signaling via reducing the expression of TNF receptor-associated factor 6 (TRAF6) and programmed cell death 4 (PDCD4), which further induced the decrease of proinflammatory cytokine expression. hDPCs forcibly overexpressing miR-21-5p downregulated the LPS-induced expression of TNF receptor-associated factor 6 (TRAF6; a component of the Toll-like receptor [TLR]/NF-κB signaling pathway), programmed cell death 4 (PDCD4, a positive regulator of the TLR/NF-κB signaling pathway), and proinflammatory cytokines. In contrast, miR-21-5p inhibitor-transfected hDPCs upregulated the expression of TRAF6, PDCD4, and inflammatory cytokines following LPS stimulation. These findings suggest that miR-21-5p expression was induced by the NF-κB signaling pathway, which was in turn negatively regulated by miR-21-5p via downregulation of TRAF6 and PDCD4 expression in LPS-stimulated hDPCs.
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Affiliation(s)
- Keisuke Nara
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Nobuyuki Kawashima
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Sonoko Noda
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Mayuko Fujii
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Kentaro Hashimoto
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Kento Tazawa
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Takashi Okiji
- Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
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Hossain MZ, Bakri MM, Yahya F, Ando H, Unno S, Kitagawa J. The Role of Transient Receptor Potential (TRP) Channels in the Transduction of Dental Pain. Int J Mol Sci 2019; 20:ijms20030526. [PMID: 30691193 PMCID: PMC6387147 DOI: 10.3390/ijms20030526] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 12/18/2022] Open
Abstract
Dental pain is a common health problem that negatively impacts the activities of daily living. Dentine hypersensitivity and pulpitis-associated pain are among the most common types of dental pain. Patients with these conditions feel pain upon exposure of the affected tooth to various external stimuli. However, the molecular mechanisms underlying dental pain, especially the transduction of external stimuli to electrical signals in the nerve, remain unclear. Numerous ion channels and receptors localized in the dental primary afferent neurons (DPAs) and odontoblasts have been implicated in the transduction of dental pain, and functional expression of various polymodal transient receptor potential (TRP) channels has been detected in DPAs and odontoblasts. External stimuli-induced dentinal tubular fluid movement can activate TRP channels on DPAs and odontoblasts. The odontoblasts can in turn activate the DPAs by paracrine signaling through ATP and glutamate release. In pulpitis, inflammatory mediators may sensitize the DPAs. They could also induce post-translational modifications of TRP channels, increase trafficking of these channels to nerve terminals, and increase the sensitivity of these channels to stimuli. Additionally, in caries-induced pulpitis, bacterial products can directly activate TRP channels on DPAs. In this review, we provide an overview of the TRP channels expressed in the various tooth structures, and we discuss their involvement in the development of dental pain.
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Affiliation(s)
- Mohammad Zakir Hossain
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Marina Mohd Bakri
- Department of Oral and Craniofacial Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Farhana Yahya
- Department of Oral and Craniofacial Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Hiroshi Ando
- Department of Biology, School of Dentistry, Matsumoto Dental University, 1780 Gobara, Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Shumpei Unno
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Junichi Kitagawa
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
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Chen E, Bakr MM, Firth N, Love RM. Inflammatory cell expression of Toll-like receptor-2 (TLR2) within refractory periapical granuloma. F1000Res 2018; 7:1819. [PMID: 30631444 PMCID: PMC6281009 DOI: 10.12688/f1000research.16678.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/01/2018] [Indexed: 12/20/2022] Open
Abstract
Background: Toll-like receptor-2 (TLR2) is highly important within the immune system. Characterization of the expression of TLR2 within inflammatory cells in periapical lesions could help in diagnosis and management of refractory cases. The aim of the study is identification of Toll-like receptor (TLR2) through immunohistochemical and immunofluroscence expression in inflammatory cells within refractory periapical granuloma cases. Methods: Eight cases of refractory periapical granuloma were selected out of 772 cases. Histological examination and immunohistochemical staining with polyclonal rabbit antihuman TLR2, monoclonal mouse antihuman CD38, CD68 and CD83 primary antibodies, as well as immunofluorescence staining with goat anti-rabbit TLR2, donkey anti-mouse CD38, CD68 and CD83 primary antibodies was conducted. Positive controls, negative controls and experimental sections with no primary antibody were included in the study. Qualitative analysis and double immunofluorescence technique was used to characterize the TLR + cells. Results: In periapical granuloma, lymphocytes (CD38 cells) expressed the most amount of TLR reactivity followed by macrophages (CD68 cells), and odontogenic epithelial cells. Neutrophils, red blood cells (RBCs) and collagen ground substance were negative to TLR2. Conclusion: TLR2 was highly expressed by lymphocytes and plasma cells indicative of their major role in the inflammatory process and antigen recognition in refractory periapical granuloma. Dendritic cells expressing TLR2 were low in number suggesting a minor role in sustaining these lesions.
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Affiliation(s)
- Eric Chen
- School of Dentistry, University of Otago, North Dunedin, Dunedin, 9016, New Zealand
| | - Mahmoud M. Bakr
- School of Dentistry and Oral Health, Griffith University, Southport, Queensland, 4215, Australia
| | - Norman Firth
- School of Dentistry, The University of Queensland, Herston, Queensland, 4006, Australia
| | - Robert M. Love
- School of Dentistry, University of Otago, North Dunedin, Dunedin, 9016, New Zealand
- School of Dentistry and Oral Health, Griffith University, Southport, Queensland, 4215, Australia
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15
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Diogenes A, Hargreaves KM. Microbial Modulation of Stem Cells and Future Directions in Regenerative Endodontics. J Endod 2018; 43:S95-S101. [PMID: 28844309 DOI: 10.1016/j.joen.2017.07.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Regenerative endodontic procedures (REPs) have been shown to promote the resolution of signs and symptoms of disease and increase survival compared with traditional treatment procedures. However, there is still variable predictability of continued root development and evidence that the tissues formed do not recapitulate the native pulp-dentin complex. There is growing evidence that the apical papilla is capable of surviving prolonged endodontic infection and apical periodontitis and that it represents a rich source of undifferentiated mesenchymal stem cells in REPs. The survival and proper differentiation of stem cells transferred into infected root canals are fraught with challenges. Residual antigens, such as lipopolysaccharides, have been shown to be present in dentin even after adequate chemomechanical debridement. These antigens have a profound effect on stem cell fate by modulating their proliferative capacity and postdifferentiation phenotype. Thus, root canals must be detoxified in addition to disinfection. There is a strong need for translational studies that incorporate all aspects of tissue engineering in endodontics in models that include an existing infection to promote further advancement of the field. This is particularly important to make REPs more predictable when treating immature teeth in young patients. Importantly, regenerative procedures could eventually promote tooth longevity in our aging population. Lessons learned from translational studies that best mimic the clinical challenges could be evaluated in pragmatic clinical trials to determine the effectiveness of these procedures to promote desirable patient-centered outcomes.
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Affiliation(s)
- Anibal Diogenes
- Department of Endodontics at University of Texas Health Science Center at San Antonio, San Antonio, Texas.
| | - Kenneth M Hargreaves
- Department of Endodontics at University of Texas Health Science Center at San Antonio, San Antonio, Texas
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16
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Yumoto H, Hirao K, Hosokawa Y, Kuramoto H, Takegawa D, Nakanishi T, Matsuo T. The roles of odontoblasts in dental pulp innate immunity. JAPANESE DENTAL SCIENCE REVIEW 2018; 54:105-117. [PMID: 30128058 PMCID: PMC6094490 DOI: 10.1016/j.jdsr.2018.03.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 02/06/2018] [Accepted: 03/01/2018] [Indexed: 11/26/2022] Open
Abstract
Odontoblasts located in the outermost layer of dental pulp form a natural barrier between mineralized tissues, dentin, and soft tissues, dental pulp, of the vital tooth, and they first recognize caries-related pathogens and sense external irritations. Therefore, odontoblasts possess a specialized innate immune system to fight oral pathogens invading into dentin. Generally, the rapid initial sensing of microbial pathogens, especially pathogen-associated molecular patterns (PAMPs) shared by microorganisms, are mediated by pattern recognition receptors (PRRs), such as Toll-like receptor and the nucleotide-binding oligomerization domain (NOD). The innate immune responses in odontoblasts initiated by sensing oral pathogens provide host protective events, such as inflammatory reactions, to produce a variety of pro-inflammatory mediators, including chemokines and cytokines. These attract various inflammatory cells and cause antibacterial reactions, such as the production of defensins, to kill microorganisms in the proximal region of the odontoblast layer. This review focuses on innate immunity, especially cellular and molecular mechanisms regarding the sensing of PAMPs from oral pathogens by PRRs, in odontoblasts and provides information for future studies for the development of novel therapeutic strategies, including diagnosis and treatment, to prevent exceeding dental pulp inflammation and preserve the dental pulp tissues.
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Affiliation(s)
- Hiromichi Yumoto
- Department of Periodontology and Endodontology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Kouji Hirao
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Yuki Hosokawa
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Hitomi Kuramoto
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Daisuke Takegawa
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Tadashi Nakanishi
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Takashi Matsuo
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
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17
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Wu H, He M, Yang R, Zuo Y, Bian Z. Astrocyte elevated gene-1 participates in the production of pro-inflammatory cytokines in dental pulp cells via NF-κB signalling pathway. Int Endod J 2018; 51:1130-1138. [DOI: 10.1111/iej.12921] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Accepted: 02/27/2018] [Indexed: 12/23/2022]
Affiliation(s)
- H. Wu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education; School & Hospital of Stomatology; Wuhan University; Wuhan China
| | - M. He
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education; School & Hospital of Stomatology; Wuhan University; Wuhan China
| | - R. Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education; School & Hospital of Stomatology; Wuhan University; Wuhan China
| | - Y. Zuo
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education; School & Hospital of Stomatology; Wuhan University; Wuhan China
| | - Z. Bian
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education; School & Hospital of Stomatology; Wuhan University; Wuhan China
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18
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Enterococcus faecalis Demonstrates Pathogenicity through Increased Attachment in an Ex Vivo Polymicrobial Pulpal Infection. Infect Immun 2018; 86:IAI.00871-17. [PMID: 29483293 DOI: 10.1128/iai.00871-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 02/21/2018] [Indexed: 11/20/2022] Open
Abstract
This study investigated the host response to a polymicrobial pulpal infection consisting of Streptococcus anginosus and Enterococcus faecalis, bacteria commonly implicated in dental abscesses and endodontic failure, using a validated ex vivo rat tooth model. Tooth slices were inoculated with planktonic cultures of S. anginosus or E. faecalis alone or in coculture at S. anginosus/E. faecalis ratios of 50:50 and 90:10. Attachment was semiquantified by measuring the area covered by fluorescently labeled bacteria. Host response was established by viable histological cell counts, and inflammatory response was measured using reverse transcription-quantitative PCR (RT-qPCR) and immunohistochemistry. A significant reduction in cell viability was observed for single and polymicrobial infections, with no significant differences between infection types (∼2,000 cells/mm2 for infected pulps compared to ∼4,000 cells/mm2 for uninfected pulps). E. faecalis demonstrated significantly higher levels of attachment (6.5%) than S. anginosus alone (2.3%) and mixed-species infections (3.4% for 50:50 and 2.3% for 90:10), with a remarkable affinity for the pulpal vasculature. Infections with E. faecalis demonstrated the greatest increase in tumor necrosis factor alpha (TNF-α) (47.1-fold for E. faecalis, 14.6-fold for S. anginosus, 60.1-fold for 50:50, and 25.0-fold for 90:10) and interleukin 1β (IL-1β) expression (54.8-fold for E. faecalis, 8.8-fold for S. anginosus, 54.5-fold for 50:50, and 39.9-fold for 90:10) compared to uninfected samples. Immunohistochemistry confirmed this, with the majority of inflammation localized to the pulpal vasculature and odontoblast regions. Interestingly, E. faecalis supernatant and heat-killed E. faecalis treatments were unable to induce the same inflammatory response, suggesting E. faecalis pathogenicity in pulpitis is linked to its greater ability to attach to the pulpal vasculature.
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19
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Li C, Qi WT, Jiang HW. Odontoclastogenesis of mouse papilla-derived MDPC-23 cells induced by lipopolysaccharide. Int Endod J 2017; 51 Suppl 2:e115-e124. [PMID: 28333374 DOI: 10.1111/iej.12771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/18/2017] [Indexed: 11/29/2022]
Abstract
AIM To investigate the role of Lipopolysaccharide (LPS) in the odontoclast differentiation of MDPC-23 cells. It was hypothesized that MDPC-23 odontoblast-like cells may function as odontoclasts under the influence of LPS. METHODOLOGY MDPC-23 cells were cultured in the presence of 0.1 or 1 μg mL-1 LPS for 6 days. Cell viability was determined using the CCK8 assay. TRAP staining, dentine resorption assay and ROS detection by confocal laser scanning microscope were used to test the odontoclast-like function of the induced cells. In additional, the related protein expression was confirmed by Western blotting and ELISA. An unpaired Student's t-test and one-way anova were used in statistical analysis. RESULTS TRAP-positive cells, which are multinucleated, on the dentine slice were significantly increased in 1 μg mL-1 LPS-induced cells (P < 0.05). Osteoclast-specific proteins such as TRAP cathepsin K and Rac1 were upregulated in the 1 μg mL-1 LPS-treated cells (P < 0.05), whilst the expression of marker proteins of the RANKL-RANK signalling pathway (RANKL, RANK and TRAF6) in the induced cells was not significantly changed (P > 0.05). ROS production was observed in the 1 μg mL-1 LPS treatment group (P < 0.05), but no significant differences were observed in the level of RANKL in the cell supernatant between the LPS-treated group and the control group (P > 0.05). CONCLUSIONS A known value of 1 μg mL-1 LPS might induce odontoblast-like MDPC-23 cells to generate odontoclast-like cells or to function as odontoclasts. The data might provide a new explanation for the precursors of odontoclasts and root resorption.
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Affiliation(s)
- C Li
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Affiliated Stomatological Hospital, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - W T Qi
- Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou, China
| | - H W Jiang
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Affiliated Stomatological Hospital, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China
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20
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Rechenberg DK, Galicia JC, Peters OA. Biological Markers for Pulpal Inflammation: A Systematic Review. PLoS One 2016; 11:e0167289. [PMID: 27898727 PMCID: PMC5127562 DOI: 10.1371/journal.pone.0167289] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 11/11/2016] [Indexed: 12/31/2022] Open
Abstract
Background and Objective Pulpitis is mainly caused by an opportunistic infection of the pulp space with commensal oral microorganisms. Depending on the state of inflammation, different treatment regimes are currently advocated. Predictable vital pulp therapy depends on accurate determination of the pulpal status that will allow repair to occur. The role of several players of the host response in pulpitis is well documented: cytokines, proteases, inflammatory mediators, growth factors, antimicrobial peptides and others contribute to pulpal defense mechanisms; these factors may serve as biomarkers that indicate the status of the pulp. Therefore, the aim of this systematic review was to evaluate the presence of biomarkers in pulpitis. Methods The electronic databases of MEDLINE, EMBASE, Scopus and other sources were searched for English and non-English articles published through February 2015. Two independent reviewers extracted information regarding study design, tissue or analyte used, outcome measures, results and conclusions for each article. The quality of the included studies was assessed using a modification of the Newcastle-Ottawa-Scale. Results and Conclusions From the initial 847 publications evaluated, a total of 57 articles were included in this review. In general, irreversible pulpitis was associated with different expression of various biomarkers compared to normal controls. These biomarkers were significantly expressed not only in pulp tissue, but also in gingival crevicular fluid that can be collected non-invasively, and in dentin fluid that can be analyzed without extirpating the entire pulpal tissue. Such data may then be used to accurately differentiate diseased from healthy pulp tissue. The interplay of pulpal biomarkers and their potential use for a more accurate and biologically based diagnostic tool in endodontics is envisaged.
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Affiliation(s)
- Dan-Krister Rechenberg
- Department of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zürich, Zürich, Switzerland
- * E-mail:
| | - Johnah C. Galicia
- Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California, United States of America
| | - Ove A. Peters
- Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California, United States of America
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21
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Takahashi N, Nyvad B. Ecological Hypothesis of Dentin and Root Caries. Caries Res 2016; 50:422-31. [PMID: 27458979 DOI: 10.1159/000447309] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/31/2016] [Indexed: 11/19/2022] Open
Abstract
Recent advances regarding the caries process indicate that ecological phenomena induced by bacterial acid production tilt the de- and remineralization balance of the dental hard tissues towards demineralization through bacterial acid-induced adaptation and selection within the microbiota - from the dynamic stability stage to the aciduric stage via the acidogenic stage [Takahashi and Nyvad, 2008]. Dentin and root caries can also be partly explained by this hypothesis; however, the fact that these tissues contain a considerable amount of organic material suggests that protein degradation is involved in caries formation. In this review, we compiled relevant histological, biochemical, and microbiological information about dentin/root caries and refined the hypothesis by adding degradation of the organic matrix (the proteolytic stage) to the abovementioned stages. Bacterial acidification not only induces demineralization and exposure of the organic matrix in dentin/root surfaces but also activation of dentin-embedded and salivary matrix metalloproteinases and cathepsins. These phenomena initiate degradation of the demineralized organic matrix in dentin/root surfaces. While a bacterial involvement has never been confirmed in the initial degradation of organic material, the detection of proteolytic/amino acid-degrading bacteria and bacterial metabolites in dentin and root caries suggests a bacterial digestion and metabolism of partly degraded matrix. Moreover, bacterial metabolites might induce pulpitis as an inflammatory/immunomodulatory factor. Root and dentin surfaces are always at risk of becoming demineralized in the oral cavity, and exposed organic materials can be degraded by host-derived proteases contained in saliva and dentin itself. New approaches to the prevention and treatment of root/dentin caries are required.
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Affiliation(s)
- Nobuhiro Takahashi
- Division of Oral Ecology and Biochemistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
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22
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Absent in melanoma 2 (AIM2) expressed in human dental pulp mediates IL-1β secretion in response to cytoplasmic DNA. Inflammation 2015; 38:566-75. [PMID: 24986444 DOI: 10.1007/s10753-014-9963-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The inflammasome has been determined to play an important role in inflammatory diseases in recent years. Absent in melanoma 2 (AIM2), an inflammasome that recognizes cytoplasmic DNA, has recently been identified as a critical regulator of immune responses. In this study, we explored whether AIM2 was expressed in human dental pulp and defined the role of AIM2 in regulating interleukin (IL)-1β secretion. We demonstrated that AIM2 was only detected in the odontoblast layer of healthy dental pulp, whereas strong expression was observed in inflamed dental pulp. Stimulation with interferon gamma (IFN-γ) and cytoplasmic DNA significantly activated the AIM2 inflammasome and increased IL-1β secretion in human dental pulp cells (HDPCs) in a time- and dose-dependent manner. Moreover, the knockdown of AIM2 downregulated both cleaved-caspase-1 expression and IL-1β release in HDPCs. These results suggest that AIM2 expressed in human dental pulp plays an important role in the immune defense by activating the inflammasome signaling pathway.
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An Overview of Pathogen Recognition Receptors for Innate Immunity in Dental Pulp. Mediators Inflamm 2015; 2015:794143. [PMID: 26576076 PMCID: PMC4630409 DOI: 10.1155/2015/794143] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/28/2015] [Indexed: 12/16/2022] Open
Abstract
Pathogen recognition receptors (PRRs) are a class of germ line-encoded receptors that recognize pathogen-associated molecular patterns (PAMPs). The activation of PRRs is crucial for the initiation of innate immunity, which plays a key role in first-line defense until more specific adaptive immunity is developed. PRRs differ in the signaling cascades and host responses activated by their engagement and in their tissue distribution. Currently identified PRR families are the Toll-like receptors (TLRs), the C-type lectin receptors (CLRs), the nucleotide-binding oligomerization domain-like receptors (NLRs), the retinoic acid-inducible gene-I-like receptors (RLRs), and the AIM2-like receptor (ALR). The environment of the dental pulp is substantially different from that of other tissues of the body. Dental pulp resides in a low compliance root canal system that limits the expansion of pulpal tissues during inflammatory processes. An understanding of the PRRs in dental pulp is important for immunomodulation and hence for developing therapeutic targets in the field of endodontics. Here we comprehensively review recent finding on the PRRs and the mechanisms by which innate immunity is activated. We focus on the PRRs expressed on dental pulp and periapical tissues and their role in dental pulp inflammation.
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Dental Pulp Defence and Repair Mechanisms in Dental Caries. Mediators Inflamm 2015; 2015:230251. [PMID: 26538821 PMCID: PMC4619960 DOI: 10.1155/2015/230251] [Citation(s) in RCA: 270] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 08/12/2015] [Indexed: 02/08/2023] Open
Abstract
Dental caries is a chronic infectious disease resulting from the penetration of oral bacteria into the enamel and dentin. Microorganisms subsequently trigger inflammatory responses in the dental pulp. These events can lead to pulp healing if the infection is not too severe following the removal of diseased enamel and dentin tissues and clinical restoration of the tooth. However, chronic inflammation often persists in the pulp despite treatment, inducing permanent loss of normal tissue and reducing innate repair capacities. For complete tooth healing the formation of a reactionary/reparative dentin barrier to distance and protect the pulp from infectious agents and restorative materials is required. Clinical and in vitro experimental data clearly indicate that dentin barrier formation only occurs when pulp inflammation and infection are minimised, thus enabling reestablishment of tissue homeostasis and health. Therefore, promoting the resolution of pulp inflammation may provide a valuable therapeutic opportunity to ensure the sustainability of dental treatments. This paper focusses on key cellular and molecular mechanisms involved in pulp responses to bacteria and in the pulpal transition between caries-induced inflammation and dentinogenic-based repair. We report, using selected examples, different strategies potentially used by odontoblasts and specialized immune cells to combat dentin-invading bacteria in vivo.
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25
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Huang Y, Jiang H, Gong Q, Li X, Ling J. Lipopolysaccharide stimulation improves the odontoblastic differentiation of human dental pulp cells. Mol Med Rep 2014; 11:3547-52. [PMID: 25528991 DOI: 10.3892/mmr.2014.3120] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 11/20/2014] [Indexed: 11/05/2022] Open
Abstract
Lipopolysaccharide (LPS) is one of the causative agents of pulpitis and previous studies have demonstrated that the LPS stimulation of human aortic valve interstitial cells induces inflammatory mediators and the gene expression of osteogenic factors. Therefore, in the present study, it was hypothesized that LPS affects the odontoblastic differentiation of human dental pulp cells (hDPCs). In order to investigate this, an in vitro study using hDPCs was performed. Increased alkaline phosphatase (ALP) activity was observed in the hDPCs treated with LPS, which was more marked when the cells were costimulated with odontogenic induction medium (OM). LPS also appeared to increase the gene expression levels of dentin sialophosphoprotein and dentin matrix protein‑1 and the protein expression level of dental sialoprotein in the hDPCs, particularly in combination with OM. In addition, the size and the number of nodules formed in the hDPCs exposed to OM and LPS were increased compared to those stimulated by OM alone. To determine the role of nuclear factor κB (NF‑κB) during the LPS‑induced odontoblastic differentiation of hDPCs, immunofluorescence was performed. The nuclear translocation of NF‑κB, induced by LPS was confirmed, suggesting its involvement in the LPS‑induced increase in odontoblastic differentiation of hDPCs. In conclusion, there may be an association between LPS stimulation, with or without OM, and odontoblastic differentiation.
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Affiliation(s)
- Yihua Huang
- Guangdong Provincial Key Laboratory of Stomatology, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology, Sun Yat‑sen University, Guangzhou, Guangdong 510055, P.R. China
| | - Hongwei Jiang
- Guangdong Provincial Key Laboratory of Stomatology, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology, Sun Yat‑sen University, Guangzhou, Guangdong 510055, P.R. China
| | - Qimei Gong
- Guangdong Provincial Key Laboratory of Stomatology, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology, Sun Yat‑sen University, Guangzhou, Guangdong 510055, P.R. China
| | - Xuyan Li
- Guangdong Provincial Key Laboratory of Stomatology, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology, Sun Yat‑sen University, Guangzhou, Guangdong 510055, P.R. China
| | - Junqi Ling
- Guangdong Provincial Key Laboratory of Stomatology, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology, Sun Yat‑sen University, Guangzhou, Guangdong 510055, P.R. China
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Muramyl dipeptide activates human beta defensin 2 and pro-inflammatory mediators through Toll-like receptors and NLRP3 inflammasomes in human dental pulp cells. Clin Oral Investig 2014; 19:1419-28. [PMID: 25467233 DOI: 10.1007/s00784-014-1361-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 11/13/2014] [Indexed: 01/01/2023]
Abstract
PURPOSE The expression levels of intracellular pyrin domain-containing 3 (NLRP3) and microbial pattern-recognition receptors, such as nucleotide-binding oligomerization domain 2 (NOD2), have been reported in human dental pulp cells (HDPCs) and inflamed dental pulp tissue, but the role of NLRP3 and Toll-like receptors (TLRs) in the production of human beta defensin 2 (hBD2) and inflammatory cytokines against invading pathogens remains poorly defined. The aim of this study was to determine whether the NOD2 ligand muramyl dipeptide (MDP) upregulates hBD2 and inflammatory cytokines and whether this response is dependent on TLRs and NLRP inflammasomes in HDPCs. METHODOLOGY The effects of MDP on the expression of hBD2, TLRs, inflammasomes, and pro-inflammatory mediators in HDPCs were examined using Western blotting and reverse transcription-polymerase chain reaction. Levels of pro-inflammatory cytokines, such as nitric oxide (NO) and prostaglandin E2 (PGE2), were determined by enzyme-linked immunosorbent assay. RESULTS MDP upregulated hBD2, TLR2, and TLR4 mRNAs and protein levels in a dose- and time-dependent manner. TLR2 and TLR4 neutralizing blocking antibodies and NOD2- and hBD2-specific small interfering RNAs (siRNAs) attenuated the MDP-induced production of NO, PGE2, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-8 and upregulated inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2) in HDPCs. Additionally, MDP activated inflammasome-related genes, such as NLRP3, caspase 1, apoptotic speck protein containing a caspase recruitment domain, and IL-1β. Furthermore, silencing of the NLRP3 gene using a siRNA significantly decreased the MDP-induced expression of hBD2 and cytokines, such as iNOS-derived NO, COX2, PGE2, TNF-α, IL-6, and IL-8. CONCLUSION These results suggest that NOD2 activates the TLR2, TLR4, and NLRP3 inflammasome-signaling pathways in HDPCs to induce the production of multiple inflammatory mediators and antimicrobial peptides, which in turn promote pulp immune defense against microbial challenge. CLINICAL RELEVANCE The TLR and NLRP3 inflammasome pathways may represent an important modulatory mechanism of immune defense responses during the progression of pulpitis. Our results suggest that local inhibition of NLRP3 and TLRs may reduce the impact of cytokine-mediated host destructive processes in pulpitis.
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Liu Y, Gao Y, Zhan X, Cui L, Xu S, Ma D, Yue J, Wu B, Gao J. TLR4 Activation by Lipopolysaccharide and Streptococcus mutans Induces Differential Regulation of Proliferation and Migration in Human Dental Pulp Stem Cells. J Endod 2014; 40:1375-81. [DOI: 10.1016/j.joen.2014.03.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 02/22/2014] [Accepted: 03/10/2014] [Indexed: 12/28/2022]
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Charadram N, Austin C, Trimby P, Simonian M, Swain MV, Hunter N. Structural analysis of reactionary dentin formed in response to polymicrobial invasion. J Struct Biol 2013; 181:207-22. [PMID: 23261402 PMCID: PMC3578079 DOI: 10.1016/j.jsb.2012.12.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 12/06/2012] [Accepted: 12/08/2012] [Indexed: 11/23/2022]
Abstract
In response to microbial invasion of dentin odontoblasts secrete an altered calcified matrix termed reactionary dentin (Rd). 3D reconstruction of focused-ion-beam scanning electron microscopy (FIB-SEM) image slices revealed helical tubular structures in Rd that contrasted with regular cylindrical tubules characteristic of dentin from healthy teeth and affected so-called physiological dentin (Pd) lying exterior to Rd. This helical structure in Rd provided effective constriction of tubule lumen diameter that formed a barrier to bacterial advance towards the dental pulp. SEM of resin cast preparations revealed altered extension of odontoblast processes through Rd. The distribution of key mineral elements was studied by combination of 3D reconstruction of focused-ion-beam based X-ray microanalysis (FIB-EDS), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). There was a marked redistribution of calcium and phosphorous in Rd together with an increase of diffusely deposited magnesium compatible with the mineral deposition phase of synthesis of this altered matrix. Changes in tubule structure and mineral content characteristic of Rd are consistent with reduced hardness and lower elastic modulus reported for this matrix. Findings provide insight into the unique structure of Rd synthesised as a primary response to infection.
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Affiliation(s)
- Nattida Charadram
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - Christine Austin
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Elemental Bio-imaging Facility, Department of Chemistry and Forensic Science, University of Technology Sydney, New South Wales, Australia
| | - Patrick Trimby
- Australian Centre For Microscopy & Microanalysis, University of Sydney, Sydney, New South Wales, Australia
| | - Mary Simonian
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
| | - Michael V. Swain
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - Neil Hunter
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
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Lang ML, Zhu L, Kreth J. Keeping the bad bacteria in check: interactions of the host immune system with oral cavity biofilms. ACTA ACUST UNITED AC 2012. [DOI: 10.1111/j.1601-1546.2012.00278.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Tjäderhane L, Haapasalo M. The dentin-pulp border: a dynamic interface between hard and soft tissues. ACTA ACUST UNITED AC 2012. [DOI: 10.1111/j.1601-1546.2012.00266.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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He W, Qu T, Yu Q, Wang Z, Wang H, Zhang J, Smith AJ. Lipopolysaccharide enhances decorin expression through the Toll-like receptor 4, myeloid differentiating factor 88, nuclear factor-kappa B, and mitogen-activated protein kinase pathways in odontoblast cells. J Endod 2012; 38:464-9. [PMID: 22414830 DOI: 10.1016/j.joen.2011.12.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
INTRODUCTION Lipopolysaccharide (LPS) has been shown to regulate the function of odontoblasts. However, the molecular mechanisms of the effect of LPS on odontoblasts are poorly understood. Decorin (DCN), one of the major matrix proteoglycans, is known to affect the mineralization of teeth. In this study, we investigated whether LPS can regulate the expression of DCN in odontoblasts and determined the intracellular signaling pathways triggered by LPS. METHODS The DCN messenger RNA and protein expression changes in mouse odontoblast-lineage cells (OLCs) were detected by real-time polymerase chain reaction (PCR) analysis and enzyme-linked immunosorbent assay (ELISA). Whether TLR4, myeloid differentiating factor 88 (MyD88), nuclear factor-kappa B (NF-κB), or mitogen-activated protein kinase (MAPK) pathways were involved in the LPS-induced DCN expression was determined by examined real-time PCR, ELISA, and luciferase activity assay. The activation of extracellular signal-regulated kinase (ERK), p38, and JNK in OLCs was measured by Western blot analysis. RESULTS We found that the mouse OLCs expressed DCN. DCN messenger RNA was rapidly induced by LPS in a time- and dose-dependent manner. Pretreatment with a MyD88 inhibitory peptide, a TLR4 antibody, or a specific inhibitor for NF-κB or I Kappa B alpha (IκBα) significantly inhibited LPS-induced DCN expression. Moreover, the LPS-mediated increase in κB-luciferase activity in OLCs was suppressed by the overexpression of dominant negative mutants of TLR4, MyD88, and IκBα but not by a dominant negative mutant of TLR2. In addition, LPS stimulation activated the ERK, p38, and JNK MAPK pathways. The pretreatment of OLCs with specific inhibitors of the ERK, p38, and JNK MAPK pathways markedly offset the LPS-induced up-regulation of DCN expression. CONCLUSIONS Our results show that LPS stimulation can up-regulate the gene expression of DCN via the TLR4, MyD88, NF-κB, and MAPK pathways in odontoblast cells.
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Affiliation(s)
- Wenxi He
- Department of Conservative Dentistry, School of Dentistry, The Fourth Military Medical University, Xian, China.
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Nakanishi T, Takegawa D, Hirao K, Takahashi K, Yumoto H, Matsuo T. Roles of dental pulp fibroblasts in the recognition of bacterium-related factors and subsequent development of pulpitis. JAPANESE DENTAL SCIENCE REVIEW 2011. [DOI: 10.1016/j.jdsr.2011.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Staquet MJ, Carrouel F, Keller JF, Baudouin C, Msika P, Bleicher F, Kufer T, Farges JC. Pattern-recognition Receptors in Pulp Defense. Adv Dent Res 2011; 23:296-301. [DOI: 10.1177/0022034511405390] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Initial sensing of infection is mediated by germline-encoded pattern-recognition receptors (PRRs), the activation of which leads to the expression of inflammatory mediators responsible for the elimination of pathogens and infected cells. PRRs act as immune sensors that provide immediate cell responses to pathogen invasion or tissue injury. Here, we review the expression of PRRs in human dental pulp cells, namely, receptors from the Toll-like (TLR) and Nod-like NLR families, by which cells recognize bacteria. Particular attention is given to odontoblasts, which are the first cells encountered by pathogens and represent, in the tooth, the first line of defense for the host. Understanding cellular and molecular mechanisms associated with the recognition of bacterial pathogens by odontoblasts is critical for the development of therapeutic strategies that aim at preventing excessive pulp inflammation and related deleterious effects.
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Affiliation(s)
- M.-J. Staquet
- Odontoblastes et Régénération des Tissus Dentaires, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d’Italie, F-69364 Lyon Cedex 07, France
| | - F. Carrouel
- Odontoblastes et Régénération des Tissus Dentaires, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d’Italie, F-69364 Lyon Cedex 07, France
| | - J.-F. Keller
- Odontoblastes et Régénération des Tissus Dentaires, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d’Italie, F-69364 Lyon Cedex 07, France
- Hospices Civils de Lyon, Service de Consultations et de Traitements Dentaires, Lyon, France
| | - C. Baudouin
- Laboratoires Expanscience, Département Innovation, Recherche et Développement, Epernon, France
| | - P. Msika
- Laboratoires Expanscience, Département Innovation, Recherche et Développement, Epernon, France
| | - F. Bleicher
- Odontoblastes et Régénération des Tissus Dentaires, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d’Italie, F-69364 Lyon Cedex 07, France
| | - T.A. Kufer
- Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Cologne, Germany
| | - J.-C. Farges
- Odontoblastes et Régénération des Tissus Dentaires, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d’Italie, F-69364 Lyon Cedex 07, France
- Hospices Civils de Lyon, Service de Consultations et de Traitements Dentaires, Lyon, France
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The Toll-like receptor 4 agonist monophosphoryl lipid a augments innate host resistance to systemic bacterial infection. Infect Immun 2011; 79:3576-87. [PMID: 21646453 DOI: 10.1128/iai.00022-11] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Monophosphoryl lipid A (MPLA) is a Toll-like receptor 4 (TLR4) agonist that is currently used as a vaccine adjuvant in humans. In this study, we evaluated the effect of MPLA treatment on the innate immune response to systemic bacterial infections in mice. Mice treated with MPLA after burn injury showed improved survival and less local and systemic dissemination of bacteria in a model of Pseudomonas aeruginosa burn wound infection. Prophylactic treatment with MPLA significantly enhanced bacterial clearance at the site of infection and reduced systemic dissemination of bacteria despite causing attenuation of proinflammatory cytokine production during acute intra-abdominal infection caused by cecal ligation and puncture. Administration of MPLA at 1 h after CLP also improved bacterial clearance but did not alter cytokine production. MPLA treatment increased the numbers of granulocytes, double-positive myeloid cells, and macrophages at sites of infection and increased the percentage and total numbers of myeloid cells mediating phagocytosis of bacteria. Depletion of Ly6G(+) neutrophils, but not macrophages, eliminated the ability of MPLA treatment to improve bacterial clearance. The immunomodulatory effects of MPLA were absent in TLR4-deficient mice. In conclusion, these studies show that MPLA treatment significantly augments the innate immune response to bacterial infection by enhancing bacterial clearance despite the attenuation of proinflammatory cytokine production. The enhanced bacterial clearance is mediated, in part, by increased numbers of myeloid cells with effective phagocytic functions at sites of infection and is TLR4 dependent.
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Ferraz CCR, Henry MA, Hargreaves KM, Diogenes A. Lipopolysaccharide from Porphyromonas gingivalis sensitizes capsaicin-sensitive nociceptors. J Endod 2011; 37:45-8. [PMID: 21146075 DOI: 10.1016/j.joen.2007.07.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Accepted: 07/09/2007] [Indexed: 01/31/2023]
Abstract
Although odontogenic infections are often accompanied by pain, little is known about the potential mechanisms mediating this effect. In this study we tested the hypothesis that trigeminal nociceptive neurons are directly sensitized by lipopolysaccharide (LPS) isolated from an endodontic pathogen, Porphyromonas gingivalis. In vitro studies conducted with cultures of rat trigeminal neurons demonstrated that pretreatment with LPS produced a significant increase in the capsaicin-evoked release of calcitonin gene-related peptide (CGRP) when compared with vehicle pretreatment, thus showing sensitization of the capsaicin receptor, TRPV1, by LPS. Furthermore, confocal microscopic examination of human tooth pulp samples showed the colocalization of the LPS receptor (toll-like receptor 4, TLR4) with CGRP-containing nerve fibers. Collectively, these results suggest the direct sensitization of nociceptors by LPS at concentrations found in infected canal systems as one mechanism responsible for the pain associated with bacterial infections.
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Affiliation(s)
- Caio Cezar Randi Ferraz
- Department of Endodontics, Piracicaba School of Dentistry, State University of Campinas, Piracicaba, SP, Brazil
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Diogenes A, Ferraz C, Akopian A, Henry M, Hargreaves K. LPS Sensitizes TRPV1 via Activation of TLR4 in Trigeminal Sensory Neurons. J Dent Res 2011; 90:759-64. [DOI: 10.1177/0022034511400225] [Citation(s) in RCA: 219] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Recent studies have demonstrated that the lipopolysaccharide (LPS) receptor (TLR4) is expressed in TRPV1 containing trigeminal sensory neurons. In this study, we evaluated whether LPS activates trigeminal neurons, and sensitizes TRPV1 responses via TLR4. To test this novel hypothesis, we first demonstrated that LPS binds to receptors in trigeminal neurons using competitive binding. Second, we demonstrated that LPS evoked aconcentration-dependent increase in intracellular calcium accumulation (Ca2+)i and inward currents. Third, LPS significantly sensitized TRPV1 to capsaicin measured by (Ca2+)i, release of calcitonin gene-related peptide, and inward currents. Importantly, a selective TLR4 antagonist blocked these effects. Analysis of these data, collectively, demonstrates that LPS is capable of directly activating trigeminal neurons, and sensitizing TRPV1 via a TLR4-mediated mechanism. These findings are consistent with the hypothesis that trigeminal neurons are capable of detecting pathogenic bacterial components leading to sensitization of TRPV1, possibly contributing to the inflammatory pain often observed in bacterial infections.
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Affiliation(s)
| | - C.C.R. Ferraz
- Department of Endodontics, UNICAMP, Piracicaba, São Paulo, Brazil
| | | | | | - K.M. Hargreaves
- Departments of Endodontics Pharmacology Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, Mail Code 7892, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
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Regulation of the stromal cell-derived factor-1alpha-CXCR4 axis in human dental pulp cells. J Endod 2010; 36:1499-503. [PMID: 20728717 DOI: 10.1016/j.joen.2010.05.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 05/05/2010] [Accepted: 05/19/2010] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Although the presence of the stromal cell-derived factor (SDF)-1alpha-CXCR4 axis has been reported in dental pulp tissue, little has been known about the underlying regulation of this axis in dental pulp stem cells (DPSCs). The purpose of this study was to investigate whether inflammation or hypoxia can regulate this axis in cultured human dental pulp cells (DPCs). METHODS Primary cultures of DPCs were stimulated by various concentrations of lipopolysaccharide (LPS) for 48 hours, and the production of SDF-1alpha or CXCR4 was assessed through the enzyme-linked immunosorbent assay and Western blotting, respectively. Additionally, DPCs were incubated in a hypoxic condition (1% O(2)) for 24 hours, and the cell proliferation ability was detected by methylthiazol tetrazolum assay. Quantitative reverse-transcription polymerase chain reaction (RT-PCR) was used to observe messenger RNA level changes of hypoxia inducible factor-1alpha(HIF-alpha), SDF-1alpha, and CXCR4. The effects of hypoxia on cell migration ability were further confirmed by transmigration assay. RESULTS All concentrations of LPS inhibited SDF-1alpha production except that 1 microg/mL LPS increased the expression of CXCR4. Hypoxia promoted the proliferation of DPCs in a 24-hour culture period. Quantitative RT-PCR showed that messenger RNA levels of HIF-alpha and CXCR4 increased, whereas SDF-1alpha decreased in hypoxic DPCs. Transmigration assay indicated that hypoxia increased the migration ability of DPCs. CONCLUSIONS These results suggested that inflammation and hypoxia might play an important role in regulating the SDF-1alpha-CXCR4 axis, which further recruits DPSCs to participate in reparative dentinogenesis.
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Desai SV, Love RM, Rich AM, Seymour GJ. Antigen recognition and presentation in periapical tissues: a role for TLR expressing cells? Int Endod J 2010; 44:87-99. [PMID: 21083574 DOI: 10.1111/j.1365-2591.2010.01817.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Bacteria are the prime cause of periapical diseases and root canal microbiology is a well-researched area of endodontics. Antigen-presenting cells (APCs) are present in periapical lesions of endodontic origin and play a substantial role in recognizing, processing and presenting pathogenic antigens to the adaptive immune system such as an effective and long-lasting immune response is generated against the specific pathogens. Toll-like receptors (TLRs) are germ-line encoded pathogen recognition receptors (PRR) expressed by various APCs which induce their maturation, lead to gene transcription in the nucleus and the production of several pro- and anti-inflammatory cytokines. Thirteen TLRs have been discovered, 10 of which have been identified in humans so far. Preliminary studies of dental pulp tissue have demonstrated various cell types expressing different TLRs in response to commonly encountered microorganisms. However, there is little information available regarding the expression and function of the various TLRs in human periapical lesions. This review discusses the interactions of various APCs in periapical lesions and the possible roles of different TLRs and APCs in pulp/periapical pathogen recognition and presentation to the adaptive immune system in the initiation and sustaining of periapical diseases.
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Affiliation(s)
- S V Desai
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, Dunedin, New Zealand
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Farahani RM, Nguyen KA, Simonian M, Hunter N. Adaptive calcified matrix response of dental pulp to bacterial invasion is associated with establishment of a network of glial fibrillary acidic protein+/glutamine synthetase+ cells. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:1901-14. [PMID: 20802180 DOI: 10.2353/ajpath.2010.100073] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report evidence for anatomical and functional changes of dental pulp in response to bacterial invasion through dentin that parallel responses to noxious stimuli reported in neural crest-derived sensory tissues. Sections of resin-embedded carious adult molar teeth were prepared for immunohistochemistry, in situ hybridization, ultrastructural analysis, and microdissection to extract mRNA for quantitative analyses. In odontoblasts adjacent to the leading edge of bacterial invasion in carious teeth, expression levels of the gene encoding dentin sialo-protein were 16-fold greater than in odontoblasts of healthy teeth, reducing progressively with distance from this site of the carious lesion. In contrast, gene expression for dentin matrix protein-1 by odontoblasts was completely suppressed in carious teeth relative to healthy teeth. These changes in gene expression were related to a gradient of deposited reactionary dentin that displayed a highly modified structure. In carious teeth, interodontoblastic dentin sialo-protein(-) cells expressing glutamine synthetase (GS) showed up-regulation of glial fibrillary acidic protein (GFAP). These cells extended processes that associated with odontoblasts. Furthermore, connexin 43 established a linkage between adjacent GFAP(+)/GS(+) cells in carious teeth only. These findings indicate an adaptive pulpal response to encroaching caries that includes the deposition of modified, calcified, dentin matrix associated with networks of GFAP(+)/GS(+) interodontoblastic cells. A regulatory role for the networks of GFAP(+)/GS(+) cells is proposed, mediated by the secretion of glutamate to modulate odontoblastic response.
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Affiliation(s)
- Ramin M Farahani
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Australia.
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Artificial Dental Pulp Exposure Injury Up-regulates Antigen-Presenting Cell–related Molecules in Rat Central Nervous System. J Endod 2010; 36:459-64. [DOI: 10.1016/j.joen.2009.12.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 12/09/2009] [Accepted: 12/12/2009] [Indexed: 11/23/2022]
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Botero T, Son J, Vodopyanov D, Hasegawa M, Shelburne C, Nör J. MAPK Signaling Is Required for LPS-induced VEGF in Pulp Stem Cells. J Dent Res 2010; 89:264-9. [DOI: 10.1177/0022034509357556] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Caries-induced pulpitis is typically accompanied by an increase in dental pulp microvascular density. However, the mechanisms by which dental pulp cells recognize lipopolysaccharides (LPSs) remain unclear. We hypothesized that Porphyromonas endodontalis and Escherichia coli LPSs induce vascular endothelial growth factor (VEGF) expression in dental pulp stem cells (DPSC) and human dental pulp fibroblasts (HDPF) through mitogen-activated protein kinase (MAPK) signaling. ELISA, semi-quantitative RT-PCR, immunofluorescence, and Western blots were used. Here, we observed that LPSs induced VEGF expression in DPSC and HDPF cells, and both cell types express Toll-like receptor 4 (TLR- 4). Notably, LPS-induced VEGF is associated with phosphorylation of protein kinase C (PKC ζ) and extracellular signal-regulator kinase (ERK1/2) and is dependent upon MAPK activation. Analysis of these data, collectively, unveils a signaling pathway responsible for synthesis of VEGF by pulp cells and suggests a novel therapeutic target for the management of vascular responses in teeth with pulpitis.
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Affiliation(s)
- T.M. Botero
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
| | - J.S. Son
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
| | - D. Vodopyanov
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
| | - M. Hasegawa
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
| | - C.E. Shelburne
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
| | - J.E. Nör
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 N. University, Rm. 1376 D, Ann Arbor, Michigan 48109-1078, USA
- Department of Pathology, University of Michigan Medical School,
- Department of Biology and Materials Sciences, University of Michigan School of Dentistry,
- Department of Biomedical Engineering, University of Michigan College of Engineering,
- University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 48109, USA
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Mutoh N, Watabe H, Chieda K, Tani-Ishii N. Expression of Toll-like receptor 2 and 4 in inflamed pulp in severe combined immunodeficiency mice. J Endod 2009; 35:975-80. [PMID: 19567318 DOI: 10.1016/j.joen.2009.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2008] [Revised: 04/04/2009] [Accepted: 04/08/2009] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Toll-like receptors (TLRs) are important receptors mediating innate immune responses because they detect factors released from bacterial cell wall components during inflammatory reactions. However, the role of TLRs in dental pulp, which is bounded by hard tissues, is poorly understood. The purpose of this study was to investigate the relationship between the innate immune system and the defense of pulp tissue by using immunodeficient mice that lack an adaptive immune response METHODS Mice with severe combined immunodeficiency (SCID) were used as a model because they lack an adaptive immune response. The expression of TLR-2 and TLR-4 in experimentally inflamed pulps in SCID mice was measured by quantitative real-time polymerase chain reaction and immunohistochemistry. Total RNA was isolated from pulp tissues at 0 to 24 hours after bacterial dentinal infection. Anti-TLR-2, anti-TLR-4 cells, anti-CD64, and antinestin cells were detected with labeled streptavidin-biotin methods. RESULTS TLR-2 messenger RNA was detected at 3 hours after bacterial infection and then gradually increased from 9 to 24 hours. Numerous TLR-2- and CD64-positive cells detected on macrophages and dendritic-like cells, and TLR-4- and CD64-positive macrophages were detected in the early stage of pulpitis. CONCLUSION These results suggest that the expression of TLR-2 and TLR-4 may be triggered by bacterial infection in irreversible pulpitis without a need for an adaptive immune response. Those signals may relate to pulpal responses to bacterial infection.
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Affiliation(s)
- Noriko Mutoh
- Department of Oral Medicine, Division of Endodontics, Kanagawa Dental College, Yokosuka, Japan
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43
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Hirao K, Yumoto H, Takahashi K, Mukai K, Nakanishi T, Matsuo T. Roles of TLR2, TLR4, NOD2, and NOD1 in Pulp Fibroblasts. J Dent Res 2009; 88:762-7. [DOI: 10.1177/0022034509341779] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Pulp fibroblasts express various pro-inflammatory mediators leading to marked infiltration of inflammatory cells in the progression of pulpitis. We hypothesized that pulp fibroblasts play roles in the recognition of invaded caries-related bacteria and the subsequent innate immune responses. We found clear expressions of TLR2, NOD1, and NOD2 and a faint expression of TLR4 in human dental pulp fibroblasts (HDPF) by RT-PCR and flow cytometry. We also observed that various pro-inflammatory mediators, including cytokines, chemokines, adhesion molecules, prostaglandin E2 and its key enzyme COX-2, not iNOS or caspase-1, were markedly up-regulated by stimulation with these TLR and NOD agonists. More over, the NOD2 agonist acted synergistically with the TLR2, not the TLR4, agonist to stimulate the production of pro-inflammatory mediators in HDPF. These findings indicate that TLR2, TLR4, NOD2, and NOD1 in HDPF are functional receptors, and NOD2 is a modulator of signals transmitted through TLR2 in pulpal immune responses, leading to progressive pulpitis.
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Affiliation(s)
- K. Hirao
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
| | - H. Yumoto
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
| | - K. Takahashi
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
| | - K. Mukai
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
| | - T. Nakanishi
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
| | - T. Matsuo
- Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8504, Japan
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Farges JC, Keller JF, Carrouel F, Durand SH, Romeas A, Bleicher F, Lebecque S, Staquet MJ. Odontoblasts in the dental pulp immune response. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2009; 312B:425-36. [DOI: 10.1002/jez.b.21259] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Noguchi F, Kitamura C, Nagayoshi M, Chen KK, Terashita M, Nishihara T. Ozonated Water Improves Lipopolysaccharide-Induced Responses of an Odontoblast-like Cell Line. J Endod 2009; 35:668-72. [DOI: 10.1016/j.joen.2009.01.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 01/19/2009] [Accepted: 01/28/2009] [Indexed: 02/04/2023]
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46
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Quantification of Endotoxins and Cultivable Bacteria in Root Canal Infection before and after Chemomechanical Preparation with 2.5% Sodium Hypochlorite. J Endod 2008; 34:268-72. [DOI: 10.1016/j.joen.2007.11.015] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 11/07/2007] [Accepted: 11/12/2007] [Indexed: 12/19/2022]
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47
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Mutoh N, Tani-Ishii N, Tsukinoki K, Chieda K, Watanabe K. Expression of Toll-like Receptor 2 and 4 in Dental Pulp. J Endod 2007; 33:1183-6. [PMID: 17889686 DOI: 10.1016/j.joen.2007.05.018] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Revised: 05/21/2007] [Accepted: 05/24/2007] [Indexed: 11/21/2022]
Abstract
Toll-like receptors (TLRs) are important factors in innate immune responses because they mediate signals from bacterial cell wall components during inflammatory reactions. However, the role of TLR in dental pulp, which is bounded by hard tissues, is little understood. The present study investigated the expression of TLR-2 and TLR-4 in experimentally inflamed pulp by quantitative real-time polymerase chain reaction and immunohistochemistry. Total RNA isolated from pulp tissue from 0 to 72 hours after bacterial dentinal infection. The TLR-2 messenger RNA (mRNA) level was 30-fold higher than the TLR-4 mRNA level at 9 hours. The TLR-2 mRNA level in pulp began to increase by 3 hours after bacterial infection, reaching a maximum level after 9 hours and gradually decreasing from 9 to 72 hours. Numerous TLR-2- and CD64-positive cells detected on macrophage and dendritic-like cells, TLR-4-positive cells detected a little in the pulp at 9 hours. These results suggest that TLR-2 may be mainly regulated during the early stage of pulp inflammation triggered by bacterial infection.
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Affiliation(s)
- Noriko Mutoh
- Department of Maxillofacial Diagnostic Science, Division of Pathology, Kanagawa Dental College, Kanagawa, Japan
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48
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Nomiyama K, Kitamura C, Tsujisawa T, Nagayoshi M, Morotomi T, Terashita M, Nishihara T. Effects of Lipopolysaccharide on Newly Established Rat Dental Pulp–derived Cell Line with Odontoblastic Properties. J Endod 2007; 33:1187-91. [PMID: 17889687 DOI: 10.1016/j.joen.2007.05.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Revised: 05/18/2007] [Accepted: 05/24/2007] [Indexed: 01/09/2023]
Abstract
To clarify mechanisms of pulp wound healing and regeneration, it is important to establish continuous odontoblast-lineage cell lines. In this study, we established the proliferating pulp progenitor cell lines from dental papilla cells of rat incisor. These cell lines showed high levels of alkaline phosphatase (ALP) activity, expression of Runx2 and dentin sialophosphoprotein (DSPP), and extracellular formation of mineralized nodules. By using the cell line with high expression level of DSPP and the prominent mineral deposition, we examined whether bacterial lipopolysaccharide (LPS) had effects on its odontoblastic properties and found that ALP activity, expression of DSPP and Runx2, and the formation of mineralized nodules were suppressed in LPS dose-dependent manner. These results indicate that our established pulp progenitor cell line exhibits odontoblastic properties, which were suppressed by LPS, suggesting that gram-negative bacterial infection might downregulate the odontoblast function.
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Affiliation(s)
- Kimiko Nomiyama
- Department of Health Promotion, Division of Infections and Molecular Biology, Kyushu Dental College, Fukuoka, Japan
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