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Nam OH, Kim JH, Kang SW, Chae YK, Jih MK, You HH, Koh JT, Kim Y. Ginsenoside Rb1 alleviates lipopolysaccharide-induced inflammation in human dental pulp cells via the PI3K/Akt, NF-κB, and MAPK signalling pathways. Int Endod J 2024; 57:759-768. [PMID: 38436525 DOI: 10.1111/iej.14058] [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: 12/16/2021] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 03/05/2024]
Abstract
AIM Among numerous constituents of Panax ginseng, a constituent named Ginsenoside Rb1 (G-Rb1) has been studied to diminish inflammation associated with diseases. This study investigated the anti-inflammatory properties of G-Rb1 on human dental pulp cells (hDPCs) exposed to lipopolysaccharide (LPS) and aimed to determine the underlying molecular mechanisms. METHODOLOGY The KEGG pathway analysis was performed after RNA sequencing in G-Rb1- and LPS-treated hDPCs. Reverse-transcription polymerase chain reaction (RT-PCR) and western blot analysis were used for the assessment of cell adhesion molecules and inflammatory cytokines. Statistical analysis was performed with one-way ANOVA and the Student-Newman-Keuls test. RESULTS G-Rb1 did not exhibit any cytotoxicity within the range of concentrations tested. However, it affected the levels of TNF-α, IL-6 and IL-8, as these showed reduced levels with exposure to LPS. Additionally, less mRNA and protein expressions of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were shown. With the presence of G-Rb1, decreased levels of PI3K/Akt, phosphorylated IκBα and p65 were also observed. Furthermore, phosphorylated ERK and JNK by LPS were diminished within 15, 30 and 60 min of G-Rb1 exposure; however, the expression of non-phosphorylated ERK and JNK remained unchanged. CONCLUSIONS G-Rb1 suppressed the LPS-induced increase of cell adhesion molecules and inflammatory cytokines, while also inhibiting PI3K/Akt, phosphorylation of NF-κB transcription factors, ERK and JNK of MAPK signalling in hDPCs.
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Affiliation(s)
- Ok Hyung Nam
- Department of Pediatric Dentistry, School of Dentistry, Kyung Hee University, Seoul, Korea
- Department of Pediatric Dentistry, Kyung Hee University College of Dentistry, Kyung Hee Universtiy Medical Center, Seoul, Korea
| | - Jae-Hwan Kim
- Department of Pediatric Dentistry, School of Dentistry, Jeonbuk National University, Jeonju, Korea
| | - Si Won Kang
- Department of Oral Pathology, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Yong Kwon Chae
- Department of Pediatric Dentistry, Kyung Hee University College of Dentistry, Kyung Hee Universtiy Medical Center, Seoul, Korea
| | - Myeong-Kwan Jih
- Department of Pediatric Dentistry, School of Dentistry, Chosun University, Gwangju, Korea
| | - Hyekyoung Hannah You
- Department of Oral Pathology, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, Hard-tissue Biointerface Research Center, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - Young Kim
- Department of Oral Pathology, School of Dentistry, Chonnam National University, Gwangju, Korea
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Tian X, Zhang P, Liu F, Yang L, Fu K, Gan K, Liu C. MicroRNA-4691-3p inhibits the inflammatory response by targeting STING in human dental pulp cells: A laboratory investigation. Int Endod J 2023; 56:1328-1336. [PMID: 37403426 DOI: 10.1111/iej.13953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/06/2023]
Abstract
AIM The regulation of human dental pulp inflammation is not fully understood. This study aims to investigate the effect of miR-4691-3p on the cGAS-STING signalling cascade and its downstream cytokines production in human dental pulp cells (HDPCs). METHODOLOGY Normal dental pulp tissue and pulp tissue with irreversible pulpitis from third molars were collected. HDPCs were isolated from pulp tissue. The expression of STING mRNA and miR-4691-3p was measured by quantitative real-time PCR. Bioinformatic computation via TargetScanHuman 8.0 and a luciferase reporter assay was used to identify the targets of miR-4691-3p. A miR-4691-3p mimic and inhibitor were used to upregulate or downregulate miR-4691-3p expression in HDPCs. HDPCs were transfected with c-di-AMP, c-di-GMP, cGAMP, interferon stimulatory DNA (ISD) and bacterial genomic DNA. Immunoblot was performed to detect the phosphorylation of TBK1, p65 and IRF3. Enzyme-linked immunoassay was performed to detect the cytokines including IFN-β, TNF or IL-6 downstream of cGAS-STING. RESULTS MiR-4691-3p expression was increased in human dental pulp tissue with irreversible pulpitis. Treatment of HDPCs using recombinant human IFN-β, TNF or IL-6 also upregulated miR-4691-3p. The bioinformatic prediction and luciferase reporter assay confirmed that STING was a direct target of miR-4691-3p. The miR-4691-3p mimic suppressed STING expression, the phosphorylation of TBK1, p65 and IRF3, and the IFN-β, TNF or IL-6 production. In contrast, the miR-4691-3p inhibitor enhanced the STING expression, the phosphorylation of TBK1, p65 and IRF3 and the IFN-β, TNF or IL-6 production. CONCLUSIONS MiR-4691-3p negatively regulates the cGAS-STING pathway by directly targeting STING. This provides insight to utilize miRNA-dependent regulatory effect to treat endodontic disease as well as STING-dependent systemic inflammatory disease.
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Affiliation(s)
- Xinxin Tian
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Ping Zhang
- Department of Pediatric Dentistry, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Fei Liu
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Lijie Yang
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Kun Fu
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Kang Gan
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Chao Liu
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
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Role of Lipopolysaccharide, Derived from Various Bacterial Species, in Pulpitis—A Systematic Review. Biomolecules 2022; 12:biom12010138. [PMID: 35053286 PMCID: PMC8774278 DOI: 10.3390/biom12010138] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/09/2022] [Accepted: 01/11/2022] [Indexed: 02/06/2023] Open
Abstract
Lipopolysaccharide (LPS) is widely used for induction of inflammation in various human tissues, including dental pulp. The purpose of this study was to summarize current medical literature focusing on (1) cell types used by researchers to simulate dental pulp inflammation, (2) LPS variants utilized in experimental settings and how these choices affect the findings. Our study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched for studies reporting outcomes of lipopolysaccharide application on dental pulp cells in vitro using electronic databases: MEDLINE, Web of Science and Scopus. Having gathered data from 115 papers, we aimed to present all known effects LPS has on different cell types present in dental pulp. We focused on specific receptors and particles that are involved in molecular pathways. Our review provides an essential foundation for further research using in vitro models of pulpitis.
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Tian X, Liu C, Wang Z. The induction of inflammation by the cGAS-STING pathway in human dental pulp cells: A laboratory investigation. Int Endod J 2021; 55:54-63. [PMID: 34570917 DOI: 10.1111/iej.13636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 01/13/2023]
Abstract
AIM To explore the presence of the cGAS-STING inflammatory pathway in human pulp tissue and human dental pulp cells (HDPCs). METHODOLOGY Pulp tissue was collected from freshly extracted human healthy third molars or third molars with irreversible pulpitis. Quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunoassay (ELISA) were performed to assess IFN-β, TNF and IL-6. Human dental pulp cells prepared from healthy human pulp tissues were transfected with interferon stimulatory DNA (ISD), bacterial genomic DNA, bacterial cyclic dinucleotides c-di-AMP, c-di-GMP or host cyclic dinucleotide cGAMP. SiRNA was used to knock down the endogenous cGAS or STING. G140 and H-151 were used to inhibit cGAS and STING respectively. Amlexanox and BAY 11-7082 were used to inhibit TBK1 and NF-κB respectively. qRT-PCR and ELISA were performed to detect the level of IFN-β, TNF and IL-6. Western blot was performed to evaluate the TBK1, IRF3 and p65 phosphorylation. The Student's t-test and one-way anova were used for statistical analysis. RESULTS IFN-β, TNF and IL-6 were up-regulated in the inflamed human dental pulp tissue. CGAS and STING mRNA were increased in the inflamed human dental pulp tissue and detected in HDPCs prepared from healthy human pulp tissues. ISD transfection induced TBK1, IRF3 and p65 phosphorylation as well as IFN-β, TNF and IL-6 production. IFN-β, TNF and IL-6 production were also induced by transfection of bacterial and host cyclic dinucleotides or bacteria DNA. ISD or bacteria DNA transfection elevated the intracellular levels of cGAMP. Knock-down of cGAS or STING, as well as using cGAS inhibitor G140 or STING inhibitor H-151 abolished the IFN-β, TNF and IL-6 production induced by ISD transfection. Knock-down of STING or using STING inhibitor H-151 abolished the IFN-β, TNF and IL-6 induction by transfection of bacterial and host cyclic dinucleotides. Both Amlexanox and BAY 11-7082 inhibited IFN-β, TNF and IL-6 production triggered by ISD and cyclic dinucleotides transfection. CONCLUSIONS Human dental pulp cells expressed an intact cGAS-STING signalling axis. The cGAS-STING signalling axis may play an important role in pulp inflammation and immune defence.
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Affiliation(s)
- Xinxin Tian
- Department of Pathogens, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China.,Stomatology Center, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Chao Liu
- Interventional Neuroradiology Department, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Zhongquan Wang
- Department of Pathogens, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
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Tian XX, Li R, Liu C, Liu F, Yang LJ, Wang SP, Wang CL. NLRP6-caspase 4 inflammasome activation in response to cariogenic bacterial lipoteichoic acid in human dental pulp inflammation. Int Endod J 2021; 54:916-925. [PMID: 33377178 DOI: 10.1111/iej.13469] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/28/2020] [Indexed: 02/05/2023]
Abstract
AIM To explore the presence and function of NLRP6-caspase 4 inflammasome in human pulp tissue and human dental pulp cells (HDPCs). METHODOLOGY Pulp tissue was collected from freshly extracted human caries-free third molars and third molars with irreversible pulpitis. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were performed to assess the expression of NLRP6-caspase 4 inflammasome. HDPCs were prepared from normal human pulp tissues and challenged with Porphyromonas gingivalis LPS. Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR were performed to assess if LPS can upregulate NLRP6 and caspase-4. HDPCs were further challenged with LPS followed with cytosolic Streptococcus mutans lipoteichoic acid (LTA). SiRNA targeting NLRP6 and Casp4 and pharmacology inhibitor Ac-FLTD-CMK and MCC950 were used to assess if Streptococcus mutans LTA can activate the NLRP6 but not the NLRP3 inflammasome. Western blot and ELISA were performed to evaluate inflammasome activation. The Student's t-test and one-way anova were used for statistical analysis. RESULTS NLRP6-caspase 4 inflammasome was upregulated and activated in inflamed human dental pulp tissue. In HDPCs, Porphyromonas gingivalis LPS upregulated the expression of NLRP6, CASP1 and CASP4 in a type I interferon dependent manner. After LPS priming, cytosolic Streptococcus mutans LTA triggered NLRP6-caspase 4 inflammasome activation. Knockdown of NLRP6 or CASP4 using siRNA or using pharmacology inhibitor Ac-FLTD-CMK but not MCC950 efficiently suppressed inflammasome activation by cytosolic LTA. CONCLUSIONS NLRP6-caspase 4 inflammasome may play an important role in pulp inflammation and immune defence. Inflammatory caspases represent a pharmacological target to restrain pulpal inflammation.
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Affiliation(s)
- X X Tian
- Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - R Li
- Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - C Liu
- Department of Interventional Neuroradiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - F Liu
- Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - L J Yang
- Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - S P Wang
- Stomatology Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - C L Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Aral K, Milward MR, Cooper PR. Dysregulation of Inflammasomes in Human Dental Pulp Cells Exposed to Porphyromonas gingivalis and Fusobacterium nucleatum. J Endod 2020; 46:1265-1272. [DOI: 10.1016/j.joen.2020.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 12/17/2022]
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In vivo temperature rise and acute inflammatory response in anesthetized human pulp tissue of premolars having Class V preparations after exposure to Polywave® LED light curing units. Dent Mater 2020; 36:1201-1213. [DOI: 10.1016/j.dental.2020.05.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/20/2020] [Accepted: 05/25/2020] [Indexed: 11/20/2022]
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8
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Nguyen V, Chen YW, Johnson JD, Paranjpe A. In Vivo Evaluation of Effect of Preoperative Ibuprofen on Proinflammatory Mediators in Irreversible Pulpitis Cases. J Endod 2020; 46:1210-1216. [DOI: 10.1016/j.joen.2020.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 05/25/2020] [Accepted: 06/09/2020] [Indexed: 01/02/2023]
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Shen S, Shang L, Liu H, Liang Q, Liang W, Ge S. AGGF1 inhibits the expression of inflammatory mediators and promotes angiogenesis in dental pulp cells. Clin Oral Investig 2020; 25:581-592. [PMID: 32789654 DOI: 10.1007/s00784-020-03498-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 08/03/2020] [Indexed: 12/20/2022]
Abstract
OBJECTIVES To determine the role of angiogenic factor with G-patch and FHA domain 1 (AGGF1) in inflammatory response of human dental pulp cells (DPCs) and the underneath mechanism and to explore its role in angiogenesis. MATERIALS AND METHODS The expression of AGGF-1 in human healthy and inflammatory pulp tissues was detected by immunohistochemistry. RT-qPCR and Western blot were used to evaluate the expression of AGGF1 in DPCs stimulated by lipopolysaccharide (LPS). After AGGF1 was knocked down, the expression of LPS-induced inflammatory cytokines in DPCs was quantified by RT-qPCR and ELISA. Immunofluorescence and Western blot were used to assess the activation of NF-κB signaling. Inflammatory cytokines were detected by RT-qPCR and ELISA in DPCs pretreated with NF-κB pathway inhibitors before LPS stimulation, and then the effect of AGGF1 on angiogenesis was also evaluated. RESULTS AGGF1 expression increased in inflammatory dental pulp tissues. In DPCs stimulated by LPS, AGGF1 was upregulated in a dose-dependent manner (P < 0.05). In AGGF1 knockdown cells, the expression of IL-6, IL-8, and monocyte chemoattractant protein-1 (MCP-1/CCL-2) increased by LPS stimulation (P < 0.001). Nuclear translocation of p65 was promoted, and the addition of NF-κB inhibitors inhibited the expression of inflammatory factors. Meanwhile, knockdown of AGGF1 inhibited vascularization. CONCLUSIONS AGGF1 inhibited the synthesis of inflammatory cytokines through NF-κB signaling pathway and promoted the angiogenesis of DPCs. CLINICAL RELEVANCE This study might shed light in the treatment of pulpitis and regeneration of dental pulp tissues; however, more clinical trials are required to validate these findings.
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Affiliation(s)
- Song Shen
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China
| | - Lingling Shang
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China
| | - Hongrui Liu
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China
| | - Qianyu Liang
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China
| | - Wei Liang
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China
| | - Shaohua Ge
- Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012, Jinan, People's Republic of China.
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IL-1β induced IL-8 and uPA expression/production of dental pulp cells: Role of TAK1 and MEK/ERK signaling. J Formos Med Assoc 2018; 117:697-704. [PMID: 29709340 DOI: 10.1016/j.jfma.2018.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/14/2018] [Accepted: 04/09/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND/PURPOSE Interleukin 1 beta (IL-1β) is a pro-inflammatory cytokine involved in the inflammatory processes of dental pulp. IL-8 and urokinase plasminogen activator (uPA) are two inflammatory mediators. However, the role of transforming growth factor beta-activated kinase-1 (TAK1) and mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathways in responsible for the effects of IL-1β on IL-8 and uPA expression/secretion of dental pulp cells are not clear. METHODS Human dental pulp cells were exposed to IL-1β with/without pretreatment with 5z-7-oxozeaneaeol (a TAK1 inhibitor) or U0126 (a MEK/ERK inhibitor). TAK1 activation was determined by immunofluorescent staining. The protein expression of IL-8 was tested by western blot. The expression of IL-8 and uPA mRNA was studied by reverse transcriptase-polymerase chain reaction (RT-PCR). The secretion of IL-8 and uPA was measured by enzyme-linked immunosorbent assay. RESULTS Exposure of dental pulp cells to IL-1β (0.1-10 ng/ml) stimulated IL-8 and uPA expression. IL-1β also induced IL-8 and uPA secretion of dental pulp cells. IL-1β stimulated p-TAK1 activation of pulp cells. Pretreatment and co-incubation of pulp cells by 5z-7oxozeaenol (1 and 2.5 μM) and U0126 (10 and 20 μM) prevented the IL-1β-induced IL-8 and uPA expression. 5z-7oxozeaenol and U0126 also attenuated the IL-1β-induced IL-8 and uPA secretion. CONCLUSION IL-1β is important in the pathogenesis of pulpal inflammatory diseases and repair via stimulation of IL-8 and uPA expression and secretion. These events are associated with TAK1 and MEK/ERK signaling. Blocking of TAK1 and MEK/ERK signaling has potential to control inflammation of dental pulp.
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11
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Anti-inflammation performance of curcumin-loaded mesoporous calcium silicate cement. J Formos Med Assoc 2017; 116:679-688. [DOI: 10.1016/j.jfma.2017.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 05/26/2017] [Accepted: 06/07/2017] [Indexed: 12/18/2022] Open
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Hirsch V, Wolgin M, Mitronin AV, Kielbassa AM. Inflammatory cytokines in normal and irreversibly inflamed pulps: A systematic review. Arch Oral Biol 2017; 82:38-46. [PMID: 28600966 DOI: 10.1016/j.archoralbio.2017.05.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/14/2017] [Indexed: 01/23/2023]
Abstract
OBJECTIVE To review the available literature in regard to the inflammatory process and pulpitis. Setting forth to evaluate if differences in the levels of various cytokines (TNF-α, IL-1β, IL-2, IL-6 and IL-8) can be observed in clinically diagnosed normal and irreversibly inflamed pulps that could serve as possible markers and/or diagnostic tools to predict and differentiate between certain states of inflammation. Methods used to measure and assess levels of cytokines have been limited to two protein quantification methods ELISA and/or Multiplex Array. DESIGN The databases PubMed, EMBASE/Ovid, The Cochrane Central Register of Controlled Trials, Cochrane Reviews and Scopus were consulted for the electronic literature search. Screening of titles and abstracts followed the PRISMA guidelines while data extraction and the assessment of the full texts were carried out in accordance to the GRADES assessment. RESULTS The review showed that significant increases in levels of IL-1β, IL-2, IL-6, IL-8 and TNF-α in irreversible pulpitis samples exist, in comparison to normal pulp samples which serve as a good basis for potential markers. Due to larger discrepancies in available literature, IL-2 seems rather unsuitable at the moment, while IL-6 and TNF alpha seem to be more promising. CONCLUSION It may be concluded that even by combining two protein quantification methods inconsistencies between studies exist. At the moment it is difficult to select just one specific cytokine suitable for testing, rather it supports the rationale that further high-quality clinical studies are needed.
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Affiliation(s)
- Vivian Hirsch
- Centre for Operative Dentistry, Periodontology, and Endodontology, University of Dental Medicine and Oral Health, Danube Private University (DPU), Steiner Landstrasse 124, 3500 Krems, Austria
| | - Michael Wolgin
- Centre for Operative Dentistry, Periodontology, and Endodontology, University of Dental Medicine and Oral Health, Danube Private University (DPU), Steiner Landstrasse 124, 3500 Krems, Austria.
| | - Aleksandr V Mitronin
- Department of Cariology and Endodontology, Moscow State University of Medicine and Dentistry (MSMSU), ul. Delegatskaya 20/1, 127473 Moscow, Russia
| | - Andrej M Kielbassa
- Centre for Operative Dentistry, Periodontology, and Endodontology, University of Dental Medicine and Oral Health, Danube Private University (DPU), Steiner Landstrasse 124, 3500 Krems, Austria
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Sueyama Y, Kaneko T, Ito T, Okiji T. Effect of lipopolysaccharide stimulation on stem cell-associated marker-expressing cells. Int Endod J 2017; 51 Suppl 2:e107-e114. [DOI: 10.1111/iej.12740] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/08/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Y. Sueyama
- Division of Cariology; Operative Dentistry and Endodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | - T. Kaneko
- Pulp Biology and Endodontics; Graduate School; Tokyo Medical and Dental University; Tokyo Japan
| | - T. Ito
- Division of Cariology; Operative Dentistry and Endodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | - T. Okiji
- Pulp Biology and Endodontics; Graduate School; Tokyo Medical and Dental University; Tokyo Japan
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Renard E, Gaudin A, Bienvenu G, Amiaud J, Farges J, Cuturi M, Moreau A, Alliot-Licht B. Immune Cells and Molecular Networks in Experimentally Induced Pulpitis. J Dent Res 2015; 95:196-205. [DOI: 10.1177/0022034515612086] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Dental pulp is a dynamic tissue able to resist external irritation during tooth decay by using immunocompetent cells involved in innate and adaptive responses. To better understand the immune response of pulp toward gram-negative bacteria, we analyzed biological mediators and immunocompetent cells in rat incisor pulp experimentally inflamed by either lipopolysaccharide (LPS) or saline solution (phosphate-buffered saline [PBS]). Untreated teeth were used as control. Expression of pro- and anti-inflammatory cytokines, chemokine ligands, growth factors, and enzymes were evaluated at the transcript level, and the recruitment of the different leukocytes in pulp was measured by fluorescence-activated cell-sorting analysis after 3 h, 9 h, and 3 d post-PBS or post-LPS treatment. After 3 d, injured rat incisors showed pulp wound healing and production of reparative dentin in both LPS and PBS conditions, testifying to the reversible pulpitis status of this model. IL6, IL1-β, TNF-α, CCL2, CXCL1, CXCL2, MMP9, and iNOS gene expression were significantly upregulated after 3 h of LPS stimulation as compared with PBS. The immunoregulatory cytokine IL10 was also upregulated after 3 h, suggesting that LPS stimulates not only inflammation but also immunoregulation. Fluorescence-activated cell-sorting analysis revealed a significant, rapid, and transient increase in leukocyte levels 9 h after PBS and LPS stimulation. The quantity of dendritic cells was significantly upregulated with LPS versus PBS. Interestingly, we identified a myeloid-derived suppressor cell–enriched cell population in noninjured rodent incisor dental pulp. The percentage of this population, known to regulate immune response, was higher 9 h after inflammation triggered with PBS and LPS as compared with the control. Taken together, these data offer a better understanding of the mechanisms involved in the regulation of dental pulp immunity that may be elicited by gram-negative bacteria.
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Affiliation(s)
- E. Renard
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
| | - A. Gaudin
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
- Faculty of Odontology, University of Nantes, Nantes, France
| | - G. Bienvenu
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
- Faculty of Odontology, University of Nantes, Nantes, France
| | | | - J.C. Farges
- Laboratory of Tissue Biology and Therapeutic Engineering, UMR 5305, and Faculty of Odontology, Lyon, France
| | - M.C. Cuturi
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
| | - A. Moreau
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
| | - B. Alliot-Licht
- INSERM, Center for Research in Transplantation and Immunology, UMR 1064, Nantes, France
- Faculty of Odontology, University of Nantes, Nantes, France
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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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Yang HH, Jun HK, Jung YJ, Choi BK. Enterococcus faecalis activates caspase-1 leading to increased interleukin-1 beta secretion in macrophages. J Endod 2014; 40:1587-92. [PMID: 25127933 DOI: 10.1016/j.joen.2014.06.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 05/27/2014] [Accepted: 06/21/2014] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Recent studies of inflammasome activation have focused on the pathogenesis of diverse inflammatory and autoimmune diseases. Inflammasome activation results in caspase-1 activation, which is required for processing of prointerleukin (IL)-1 beta to its secreted form as well as a proinflammatory cell death (ie, pyroptosis). The purpose of this study was to analyze whether Enterococcus faecalis associated with endodontic infection induces inflammasome activation. METHODS THP-1 macrophages were treated with E. faecalis in the presence or absence of caspase-1 inhibitors. Caspase-1 activation, pro-IL-1 beta expression, and IL-1 beta secretion were detected by immunoblotting, real-time reverse-transcription polymerase chain reaction, and enzyme-linked immunosorbent assay, respectively. Cell death was measured by lactate dehydrogenase release and propidium iodide staining. Adenosine triphosphate (ATP) release was measured by an ATP bioluminescence assay kit. RESULTS E. faecalis induced caspase-1 activation and pro-IL-1 beta expression, which resulted in IL-1 beta secretion in macrophages. E. faecalis significantly induced ATP release, which is a mechanism of Nod-like receptor family protein 3 (NLRP3) inflammasome activation, whereas oxATP treatment inhibited E. faecalis-induced caspase-1 activation. E. faecalis significantly increased lactate dehydrogenase release and propidium iodide uptake, which are characteristics of pyroptosis. CONCLUSIONS Our results show that E. faecalis may contribute to the progression of pulpal inflammation by stimulating excessive secretion of IL-1 beta and cell death.
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Affiliation(s)
- Ha-Hymn Yang
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Hye-Kyoung Jun
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Young-Jung Jung
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Bong-Kyu Choi
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Republic of Korea; Dental Research Institute, Seoul National University, Seoul, Republic of Korea.
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17
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Kim DS, Shin MR, Kim YS, Bae WJ, Roh DH, Hwang YS, Kim EC. Anti-inflammatory effects of glutamine on LPS-stimulated human dental pulp cells correlate with activation of MKP-1 and attenuation of the MAPK and NF-κB pathways. Int Endod J 2014; 48:220-8. [PMID: 24766418 DOI: 10.1111/iej.12303] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/23/2014] [Indexed: 01/14/2023]
Abstract
AIM To evaluate the anti-inflammatory effects of glutamine and the underlying signal pathway mechanisms in lipopolysaccharide (LPS)-stimulated human dental pulp cells (HDPCs). METHODS Human dental pulp cells were exposed to 10 μg mL(-1) LPS and various concentrations of glutamine for 24 h. The production of PGE2 and nitric oxide was determined by enzyme-linked immunosorbent assay (ELISA) and Griess reagent kit, respectively. Cytokines were examined by ELISA, reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time PCR. iNOS and COX protein expression as well as signal pathways were accessed by Western blot. The data were analysed by anova with Bonferroni's test (α = 0.05). RESULTS Glutamine reduced LPS-induced iNOS and COX-2 protein expression as well as production of NO and PGE2 in a dose-dependent fashion. Additionally, glutamine suppressed the production and mRNA expression of inflammatory cytokines including interleukin-1β (IL-1β), TNF-α, and IL-8. Furthermore, glutamine attenuated phosphorylation of extracellular signal-regulated kinase (ERK), p38, c-Jun N-terminal kinase (JNK) and IκB-α, and nuclear translocation of NF-κB p65, but enhanced mitogen-activated protein kinase phosphatase-1 (MKP-1) expression in LPS-treated HDPCs. CONCLUSION Glutamine exerted an anti-inflammatory effect via activation of MKP-1 and inhibition of the NF-κB and MAPK pathways in LPS-treated HDPCs.
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Affiliation(s)
- D-S Kim
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Korea
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18
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Mirucki CS, Abedi M, Jiang J, Zhu Q, Wang YH, Safavi KE, Clark RB, Nichols FC. Biologic activity of porphyromonas endodontalis complex lipids. J Endod 2014; 40:1342-8. [PMID: 25146013 DOI: 10.1016/j.joen.2014.02.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/21/2014] [Accepted: 02/22/2014] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Periapical infections secondary to pulpal necrosis are associated with bacterial contamination of the pulp. Porphyromonas endodontalis, a gram-negative organism, is considered to be a pulpal pathogen. P. gingivalis is phylogenetically related to P. endodontalis and synthesizes several classes of novel complex lipids that possess biological activity, including the capacity to promote osteoclastogenesis and osteoclast activation. The purpose of this study was to extract and characterize constituent lipids of P. endodontalis and evaluate their capacity to promote proinflammatory secretory responses in the macrophage cell line, RAW 264.7, as well as their capacity to promote osteoclastogenesis and inhibit osteoblast activity. METHODS Constituent lipids of both organisms were fractionated by high-performance liquid chromatography and were structurally characterized using electrospray mass spectrometry or electrospray-mass spectrometry/mass spectrometry. The virulence potential of P. endodontalis lipids was then compared with known biologically active lipids isolated from P. gingivalis. RESULTS P. endodontalis total lipids were shown to promote tumor necrosis factor alpha secretion from RAW 264.7 cells, and the serine lipid fraction appeared to account for the majority of this effect. P. endodontalis lipid preparations also increased osteoclast formation from RAW 264.7 cells, but osteoblast differentiation in culture was inhibited and appeared to be dependent on Toll-like receptor 2 expression. CONCLUSIONS These effects underscore the importance of P. endodontalis lipids in promoting inflammatory and bone cell activation processes that could lead to periapical pathology.
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Affiliation(s)
- Christopher S Mirucki
- Division of Endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Mehran Abedi
- Division of Endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Jin Jiang
- Division of Endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Qiang Zhu
- Division of Endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Yu-Hsiung Wang
- Division of Pediatric Dentistry, Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Kamran E Safavi
- Division of Endodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Robert B Clark
- Department of Immunology, University of Connecticut School of Medicine, University of Connecticut Health Center, Farmington, Connecticut
| | - Frank C Nichols
- Division of Periodontology, Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Connecticut.
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An evaluation of the inflammatory response of lipopolysaccharide-treated primary dental pulp cells with regard to calcium silicate-based cements. Int J Oral Sci 2014; 6:94-8. [PMID: 24556955 PMCID: PMC5130057 DOI: 10.1038/ijos.2014.5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2013] [Indexed: 01/23/2023] Open
Abstract
This study compared the biological changes of lipopolysaccharide (LPS)-treated dental pulp (DP) cells directly cultured on mineral trioxide aggregate (MTA) and calcium silicate (CS) cements. DP cells were treated with LPS for 24 h. Then, the LPS-treated DP cells were cultured on MTA or CS cements. Cell viability, cell death mechanism and interleukin (IL)-1β expressions were analysed. A one-way analysis of variance was used to evaluate the significance of the differences between the means. A significantly higher IL-1β expression (2.9-fold) was found for LPS-treated cells (P<0.05) compared with DP cells without LPS treatment at 24 h. Absorbance values of LPS-treated cells cultured on CS cement were higher than a tissue culture plate. A significant difference (P<0.05) in cell viability was observed between cells on CS and MTA cements 24 h after seeding. At 48 h, a high concentration of Si (5 mM) was released from MTA, which induced LPS-treated DP cell apoptosis. The present study demonstrates that CS cement is biocompatible with cultured LPS-treated DP cells. MTA stimulates inflammation in LPS-treated DP cells, which leads to greater IL-1β expression and apoptosis.
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Neiva KG, Catalfamo DL, Holliday LS, Wallet SM, Pileggi R. Propolis decreases lipopolysaccharide-induced inflammatory mediators in pulp cells and osteoclasts. Dent Traumatol 2014; 30:362-367. [PMID: 24502251 DOI: 10.1111/edt.12096] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND Intracanal medicaments are used to disinfect the root canal system, reduce interappointment pain and inflammation, and prevent resorption. Bacterial components such as lipopolysaccharide (LPS) are implicated in the development of pulpal and periapical inflammation and inducing osteoclastogenesis. Propolis is a natural, non-toxic substance collected from bee's wax that has been used for many years in folk medicine. Propolis has been demonstrated to have antibacterial and anti-inflammatory properties. Our previous studies have shown that propolis inhibits osteoclast maturation. However, the effect of propolis on the inflammatory response of pulp cells and osteoclasts has not been explored. AIM The purpose of this study was to evaluate whether propolis alters the inflammatory response of three endodontically relevant cell lines: mouse odontoblast-like cells (MDPC-23), macrophages (RAW264.7), and osteoclasts. MATERIAL AND METHODS Cells were exposed to 0-20 ug ml(-1) LPS to induce an inflammatory response, in the presence of propolis or vehicle control. Culture supernatants were collected after 6 and 24 h, and expression of multiple soluble mediators was determined using Luminex(®) multiplex technology. RESULTS Propolis was effective in reducing secretion of the LPS-induced inflammatory cyto/chemokines: IL-1α, IL-6, IL-12(p70), IL-15, G-CSF, TNF-α, MIP-1α, MCP-1, and IP-10. CONCLUSION Our results demonstrate that propolis suppresses the LPS-induced inflammatory response of key cells within the root canal system.
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Affiliation(s)
- Kathleen G Neiva
- Department of Endododntics, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Dana L Catalfamo
- Department of Periodontology and Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - L Shannon Holliday
- Department of Orthodontics, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Shannon M Wallet
- Department of Periodontology and Oral Biology, University of Florida College of Dentistry, Gainesville, FL, USA
| | - Roberta Pileggi
- Department of Endododntics, University of Florida College of Dentistry, Gainesville, FL, USA
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Ketoprofen Inhibits Expression of Inflammatory Mediators in Human Dental Pulp Cells. J Endod 2013; 39:764-7. [DOI: 10.1016/j.joen.2013.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 02/13/2013] [Accepted: 02/15/2013] [Indexed: 11/23/2022]
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Song Z, Lin Z, He F, Jiang L, Qin W, Tian Y, Wang R, Huang S. NLRP3 is expressed in human dental pulp cells and tissues. J Endod 2012; 38:1592-7. [PMID: 23146643 DOI: 10.1016/j.joen.2012.09.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 09/20/2012] [Accepted: 09/24/2012] [Indexed: 01/26/2023]
Abstract
INTRODUCTION One of the best-characterized Nod-like receptor (NLR) family members is pyrin domain containing 3 (NLRP3). Intracellular NLRP3 is the most versatile innate immune receptor. On activation, NLRP3 assembles into a multiprotein complex, termed an inflammasome, which regulates the secretion and bioactivity of interleukin-1 family cytokines. NLRP3 has broad specificity for mediating an immune response to a wide range of microbial stimuli or danger signals. Therefore, we hypothesize that NLRP3 plays an essential role in the detection of bacterial pathogens and the initiation of inflammation within the dental pulp. Thus, the aim of this study was to evaluate the expression of NLRP3 in normal human dental pulp cells (HDPCs) and pulp tissues. METHODS Pulp tissues were collected from freshly extracted human third molars, and HDPCs were prepared from the explants of normal dental pulp tissues. Reverse transcription-polymerase chain reaction and Western blotting were performed to detect the levels of NLRP3 mRNA and protein, respectively. In addition, immunohistochemical staining was used to determine the distribution of NLRP3 in pulp tissues. RESULTS Normal human dental pulp tissues displayed high levels of NLRP3 mRNA and protein. NLRP3 proteins were principally expressed in odontoblasts and some pulp vascular endothelial cells. Moreover, HDPCs also expressed NLRP3 but at a relatively low level in comparison with that of dental pulp tissues. CONCLUSIONS The expression of NLRP3 in HDPCs and pulp tissues suggests that NLRP3-mediated signaling pathways may play an important role in dental immune defense.
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Affiliation(s)
- Zhi Song
- Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
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Petrini M, Ferrante M, Ciavarelli L, Brunetti L, Vacca M, Spoto G. Prostaglandin E2 to diagnose between reversible and irreversible pulpitis. Int J Immunopathol Pharmacol 2012; 25:157-63. [PMID: 22507328 DOI: 10.1177/039463201202500118] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The aim of this work is to verify a correlation between the grade of inflammation and the concentration of PGE2 in human dental pulp. A total of 25 human dental pulps were examined by histological analysis and radioimmunologic dosage of PGE2. The pulps used in this experiment were from healthy and symptomatic teeth; the first ones were collected from teeth destined to be extracted for orthodontic reasons. An increase was observed of PGE2 in reversible pulpitis compared with healthy pulps and with the irreversible pulpitis and the clear decrease of these when NSAIDs are taken. This study demonstrates that PGE2 level is correlated to histological analysis thus allowing to distinguish symptomatic teeth in reversible and irreversible pulpitis.
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Affiliation(s)
- M Petrini
- Department of Oral Sciences, Nano and Biotechnology, University G. d'Annunzio, Chieti, Italy
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24
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Yamagishi VTK, Torneck CD, Friedman S, Huang GTJ, Glogauer M. Blockade of TLR2 inhibits Porphyromonas gingivalis suppression of mineralized matrix formation by human dental pulp stem cells. J Endod 2011; 37:812-8. [PMID: 21787495 DOI: 10.1016/j.joen.2011.03.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 03/17/2011] [Accepted: 03/18/2011] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Human dental pulp stem/progenitor cells (hDPSC) can differentiate into odontoblast-like cells and express dentin sialophosphoprotein (DSPP) and osteocalcin (OCN); thus, they may be used to regenerate dentin. However, residual bacterial components in the root canal may suppress this activity. PURPOSE This study investigated the effect of a Porphyromonas gingivalis component on the expression of DSPP and OCN by stimulated hDPSCs and the influence of blockade of TLR2-mediated P. gingivalis host recognition. METHODS Stimulated hDPSCs were exposed to varying concentrations of P. gingivalis lipopolysaccharide (LPS), and the expression of DSPP and OCN was measured. Similar groups of stimulated hDPSCs were exposed to TLR2 blocking agents before exposure to LPS. RESULTS hDPSCs exposed to 5, 10, and 20 μg/mL LPS exhibited a dose-dependent reduction in the expression of DSPP (3.19 ± 0.18, 2.60 ± 0.49, and 1.15 ± 0.29, respectively) and OCN (3.51 ± 1.18, 2.60 ± 0.67 and 1.66 ± 0.89, respectively). The expression of DSPP and OCN after exposure to 20 μg/mL of LPS was significantly lower than measured for unexposed stimulated cells (analysis of variance and post hoc Tukey test, P < .05). The blockade of TLR2 using an extra- and intracellular agent affected DSPP (4.67 ± 0.97 and 5.29 ± 1.66, respectively) and OCN (5.25 ± 1.69 and 5.82 ± 2.38, respectively) expression at levels comparable to stimulated cells unexposed to 20 μg/mL LPS (6.32 ± 2.47 and 4.70 ± 1.60 for DSPP and OCN, respectively). CONCLUSIONS The suppressing effect of P. gingivalis on mineralized matrix formation by hDPSCs is confirmed, and this suppression can be moderated by TLR2 blockade.
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Cavalcanti BN, Rode SDM, França CM, Marques MM. Pulp capping materials exert an effect on the secretion of IL-1β and IL-8 by migrating human neutrophils. Braz Oral Res 2011; 25:13-8. [PMID: 21359446 DOI: 10.1590/s1806-83242011000100003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 10/21/2010] [Indexed: 01/09/2023] Open
Abstract
Pulp repair is a complex process whose mechanisms are not yet fully understood. The first immune cells to reach the damaged pulp are neutrophils that play an important role in releasing cytokines and in phagocytosis. The objective of this study was to analyze the effect of different pulp-capping materials on the secretion of interleukin-1 beta (IL-1β) and interleukin-8 (IL-8) by migrating human neutrophils. Neutrophils were obtained from the blood of three healthy donors. The experimental groups were calcium hydroxide [Ca(OH)(2)], an adhesive system (Single Bond), and mineral trioxide aggregate (MTA). Untreated cells were used as control. Transwell chambers were used in performing the assays to mimic an in vivo situation of neutrophil chemotaxis. The pulp-capping materials were placed in the lower chamber and the human neutrophils, in the upper chamber. The cells were counted and the culture medium was assayed using ELISA kits for detecting and quantifying IL-1β and IL8. The data were compared by ANOVA followed by Tukey's test (p < 0.05). The secretion of IL-8 was significantly higher in all groups in comparison to the control group (p < 0.05). The adhesive system group showed higher IL-8 than the MTA group (p < 0.05). The secretion of IL-1β was significantly greater only in the MTA group (p < 0.001). It was concluded that only MTA is able to improve the secretion of IL-1β, and all materials tested increased IL-8 secretion. These results combined with all the other biological advantages of MTA indicate that it could be considered the material of choice for dental pulp capping.
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Affiliation(s)
- Bruno Neves Cavalcanti
- Department of Restorative Dentistry, School of Dentistry, Universidade de São Paulo, São Paulo, SP, Brazil
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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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Reactive Oxygen Species Removal Activity of Davallialactone Reduces Lipopolysaccharide-induced Pulpal Inflammation through Inhibition of the Extracellular Signal-regulated kinase 1/2 and Nuclear Factor kappa B Pathway. J Endod 2011; 37:491-5. [DOI: 10.1016/j.joen.2011.01.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 01/11/2011] [Accepted: 01/15/2011] [Indexed: 01/12/2023]
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Martinho FC, Chiesa WMM, Leite FR, Cirelli JA, Gomes BP. Antigenic Activity of Bacterial Endodontic Contents from Primary Root Canal Infection with Periapical Lesions against Macrophage in the Release of Interleukin-1β and Tumor Necrosis Factor α. J Endod 2010; 36:1467-74. [DOI: 10.1016/j.joen.2010.06.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 06/21/2010] [Accepted: 06/22/2010] [Indexed: 10/19/2022]
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Silva ACO, Faria MR, Fontes A, Campos MS, Cavalcanti BN. Interleukin-1 beta and interleukin-8 in healthy and inflamed dental pulps. J Appl Oral Sci 2010; 17:527-32. [PMID: 19936537 PMCID: PMC4327685 DOI: 10.1590/s1678-77572009000500031] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 02/12/2009] [Indexed: 11/22/2022] Open
Abstract
After aggression to the dental pulp, some cells produce cytokines in order to start and control the inflammatory process. Among these cytokines, interleukin-1 beta (IL-1ß) and interleukin-8 (IL-8) emerge as important ones. Objective: The purpose of this study was to analyze the location, distribution and concentration of these cytokines in healthy and inflamed dental pulps. Material and methods: Twenty pulps, obtained from healthy third molars (n=10) and from pulpectomies (n=10) were used for the study, with half of each group used for immunohistochemistry and half for protein extraction and ELISA assays. Fibroblasts obtained from healthy dental pulps, stimulated or not by Escherichia coli lipopolysaccharide (LPS), in order to simulate aggression on the cell cultures, were also used and analyzed by ELISA for IL-1ß and IL-8 as complementary information. Data obtained from immunohistochemistry were qualitatively analyzed. Data obtained from ELISA assays (tissue and cells) were statistically treated by the t-test (p<0.05). Results: Immunohistochemically, it was observed that inflamed pulps were strongly stained for both cytokines in inflammatory cells, while healthy pulps were not immunolabeled. ELISA from tissues quantitatively confirmed the higher presence of both cytokines. Additionally, cultured pulp fibroblasts stimulated by LPS also produce more cytokines than the control cells. Conclusions: It may be concluded that inflamed pulps present higher amounts of IL-1ß and IL-8 than healthy pulps and that pulp fibroblasts stimulated by bacterial LPS produce higher levels of IL-1ß and IL-8 than the control group.
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Ihan Hren N, Ihan A. T lymphocyte activation and cytokine expression in periapical granulomas and radicular cysts. Arch Oral Biol 2008; 54:156-61. [PMID: 18990362 DOI: 10.1016/j.archoralbio.2008.09.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 09/13/2008] [Accepted: 09/21/2008] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Radicular cysts (RCs) are periapical lesions resulting in jaw bone destruction. The inflammatory dental periapical granuloma (PG) is considered to be the origin of RC formation; however the mechanism of RC development remains unclear. METHODS Cell suspension from the surgically extirpated tissue of 27 RCs and 25 PGs was obtained. Bacteriological analysis of the PG tissue samples was performed in order to define two major groups of PG according to the prevailing causative bacterial infection: the streptococcal PG (PG-S, n=10) and the anaerobe PG (PG-A, n=9) group. The inflammatory response of tissue infiltrating lymphocytes was assessed by following T lymphocyte activation (HLA-DR expression) as well as interferon gamma (IFN-gamma) and interleukin 4 (IL-4) production which were evaluated by the flow cytometry. RESULTS In comparison to RC both types of PG contained a higher proportion of activated T cells (HLA-DR) and lower proportion of IL-4 producing cells. PG-A tissue contained increased percentage of CD3 cells and increased percentage of T helper 1 (Th1) cells in comparison with PG-S. In RC the IFN-gamma production is higher than in streptococcal PG-S but similar as in PG-A. DISCUSSION Tissue infiltration by Th2 cells and IL-4 production is likely to play an etiopathogenic role in RC formation.
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Affiliation(s)
- N Ihan Hren
- Clinical Department of Maxillofacial and Oral Surgery, University Medical Centre Ljubljana, Zaloska 2, 1000 Ljubljana, Slovenia.
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Hayashi M, Ohshima T, Ohshima M, Yamaguchi Y, Miyata H, Takeichi O, Ogiso B, Ito K, Östman A, Otsuka K. Profiling of Radicular Cyst and Odontogenic Keratocyst Cytokine Production Suggests Common Growth Mechanisms. J Endod 2008; 34:14-21. [DOI: 10.1016/j.joen.2007.08.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 08/20/2007] [Accepted: 08/29/2007] [Indexed: 10/22/2022]
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Bödör C, Matolcsy A, Bernáth M. Elevated expression of Cu, Zn-SOD and Mn-SOD mRNA in inflamed dental pulp tissue. Int Endod J 2007; 40:128-32. [PMID: 17229118 DOI: 10.1111/j.1365-2591.2006.01196.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM To determine the mRNA expression levels of copper-zinc superoxide dismutase (Cu, Zn-SOD) and manganese SOD (Mn-SOD) in healthy and inflamed human dental pulp tissue. METHODOLOGY Sixteen patients with symptomatic irreversible pulpitis (eight females and eight males) were selected for study. Normal healthy pulps were removed from extracted mandibular third molar teeth from 10 systemically healthy individuals (six females and four males). QRT-PCR analysis of Cu, Zn-SOD and Mn-SOD mRNA expression was carried out in 16 cases of irreversible pulpitis and in 10 cases of systemically healthy donors. The Shapiro-Wilk's test was used to test the normality of data, whereas the Mann-Whitney U-test was used to evaluate the significance of the differences between groups. Differences in the expression levels were considered to be statistically significant for P-values <0.05. RESULTS A significant increase (P < 0.05) occurred in both Cu, Zn-SOD and Mn-SOD mRNA expression in cases of irreversible pulpitis. The increase in Mn-SOD level was significantly higher (P < 0.05) than the change observed for Cu, Zn-SOD. CONCLUSIONS The development of pulpitis is associated with elevated transcription of both Cu, Zn-SOD and Mn-SOD; pulp tissue inflammation generated higher Mn-SOD transcription compared with Cu, Zn-SOD.
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Affiliation(s)
- C Bödör
- Department of Pathology and Experimental Cancer Research, Faculty of Medicine, Semmelweis University, Budapest, Turkey
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Kawashima N, Nakano-Kawanishi H, Suzuki N, Takagi M, Suda H. Effect of NOS inhibitor on cytokine and COX2 expression in rat pulpitis. J Dent Res 2006; 84:762-7. [PMID: 16040737 DOI: 10.1177/154405910508400815] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Various kinds of chemical mediators are synthesized in the course of pulpitis; thus, control of their production would assist in inducing a reduction in pulpal inflammation. We hypothesized that nitric oxide (NO) would be an important mediator of pulpal inflammation. Pulpal inflammation was induced by the application of LPS in rat incisor pulp, and inducible nitric oxide synthase (iNOS) expression was evaluated by reverse-transcription/polymerase chain-reaction and immunohistochemical staining. After LPS application, iNOS mRNA was first detected after 3 hrs, peaked at 6 hrs, and decreased thereafter. iNOS-positive cells were macrophages and neutrophils. An NOS inhibitor caused drastic decreases in the expression of pro-inflammatory cytokines and COX2 mRNA, which was highly induced in the LPS-induced pulpitis. These results indicate that NO synthesis is related to the initiation of mediator production, and that its down-regulation should contribute to the prevention of pro-inflammatory mediator synthesis.
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Affiliation(s)
- N Kawashima
- Pulp Biology and Endodontics, Department of Restorative Sciences, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, USA.
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Wisithphrom K, Windsor LJ. The effects of tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, and transforming growth factor-beta1 on pulp fibroblast mediated collagen degradation. J Endod 2006; 32:853-61. [PMID: 16934628 DOI: 10.1016/j.joen.2006.03.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 03/16/2006] [Accepted: 03/17/2006] [Indexed: 11/16/2022]
Abstract
Dental pulp destruction is believed to be regulated, in part, by the matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs). Cytokines are believed to be important in the pathogenesis of pulpitis. This study examined the effects that TNF-alpha, IL-1beta, IL-6, and TGF-beta1 have on the collagen degradation mediated by pulp fibroblasts utilizing a cell-mediated collagen degradation assay. Reverse transcriptase-polymerase chain reaction, Western blot analyses, and zymography were utilized to examine multiple MMPs and TIMPs. The collagen degradation mediated by these cells was stimulated by these cytokines. TNF-alpha, IL-1beta, and IL-6 increased the mRNA and/or protein expression of MMP-1, MMP-2, and MMP-3. TGF-beta1 decreased MMP-1 mRNA expression, while only slightly affecting the MMP-2 and MMP-3 mRNA and/or protein. These cytokines did not affect the expression of TIMP-1 or TIMP-2. These results suggest that these cytokines affect pulp destruction, in part, by differentially regulating the MMPs and TIMPs.
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Affiliation(s)
- Kessiri Wisithphrom
- Department of Oral Biology, Indiana University School of Dentistry, Indianapolis, IN 46202, USA
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Wisithphrom K, Murray PE, Windsor LJ. Interleukin-1 α Alters the Expression of Matrix Metalloproteinases and Collagen Degradation by Pulp Fibroblasts. J Endod 2006; 32:186-92. [PMID: 16500223 DOI: 10.1016/j.joen.2005.10.055] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Matrix metalloproteinases (MMPs) and the tissue inhibitors of MMPs (TIMPs) have been suggested to play a role in dental pulp destruction. This study examined the effects of interleukin (IL)-1 alpha on pulp fibroblasts. The ability of these cells to degrade collagen was determined with or without IL-1 alpha utilizing a cell-mediated collagen degradation assay. Reverse transcriptase-polymerase chain reaction was utilized to examine the mRNA expression of multiple MMPs and TIMPs with and without IL-1 alpha, while Western blot analyses and zymography were utilized to examine their protein expression. The collagen degradation mediated by these cells was stimulated by IL-1 alpha and inhibited by MMP inhibitors. IL-1 alpha increased the mRNA expression of MMP-1 and MMP-3, as well as induced MMP-7. Western blot analyses confirmed these results. IL-1 alpha increased the secreted protein level of TIMP-1, while only slightly affected the level of TIMP-2. These results suggest that IL-1 alpha can induce pulp destruction by differentially regulating MMPs and TIMPs.
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Affiliation(s)
- Kessiri Wisithphrom
- Department of Oral Biology, Indiana University School of Dentistry, Indianapolis, Indiana 46202, USA
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36
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Miyamoto R, Tokuda M, Sakuta T, Nagaoka S, Torii M. Expression and Characterization of Vanilloid Receptor Subtype 1 in Human Dental Pulp Cell Cultures. J Endod 2005; 31:652-8. [PMID: 16123700 DOI: 10.1097/01.don.0000155259.22746.ae] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The expression of the vanilloid receptor subtype 1 (VR1, TRPV1) was detected in human dental pulp fibroblasts (PF-10) using RT-PCR, Western blotting, and immunocytochemical analysis. As revealed by ELISA, capsaicin induced IL-6 expression in PF-10 cells, and the VR1 antagonist capsazepine dose-dependently inhibited capsaicin-induced IL-6 production, indicating that capsaicin-induced IL-6 expression is related to VR1 activation. The interaction between capsaicin and mitogen-activated protein kinases (MAPKs) was investigated. The phosphorylation of p38 MAPK and c-Jun NH2-terminal kinase (JNK) were detected after capsaicin stimulation. p38 MAPK is involved in capsaicin-induced IL-6 production, as shown by the use of specific inhibitors of this kinase. The result of EMSA showed that capsaicin inhibited tumor necrosis factor-alpha (TNF-alpha)-induced nuclear factor-kappa B (NF-kappaB) activation in PF-10 cell cultures. These results suggest that the activation of VR1 plays an important role in dental pulp inflammation.
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Affiliation(s)
- Rie Miyamoto
- Department of Restorative Dentistry and Endodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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Puapichartdumrong P, Ikeda H, Suda H. Outward fluid flow reduces inward diffusion of bacterial lipopolysaccharide across intact and demineralised dentine. Arch Oral Biol 2005; 50:707-13. [PMID: 15958202 DOI: 10.1016/j.archoralbio.2004.12.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Accepted: 12/28/2004] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To examine the ability of outward fluid flow (OF) on resisting the inward diffusion of bacterial lipopolysaccharide (LPS) across the demineralised dentine (DD) in comparison with that across the intact dentine (ID). DESIGN Twenty ID discs were prepared from freshly extracted human third molars. After etching both dentine surfaces, hydraulic conductance (L(p)) of the dentine was measured. Ten dentine discs were then completely demineralised using 10% EDTA, and L(p) was re-measured. The diffusion of LPS through ID and DD was measured against the OF and compared to the non-outward flow (NF) (n = 5 for each group) at 0, 1, 4 and 8h. Longitudinal sections of ID and DD surfaces were observed under a scanning electron microscope (SEM). RESULTS The L(p) of DD was significantly higher than that of ID (independent t-test, p < 0.001). The application of OF and demineralisation significantly affected LPS diffusion (two-way ANOVA, p < 0.05). In addition, the effect of OF depended on dentine demineralisation. SEM images of ID showed intact dentinal tubules, whereas those of DD showed expanded collagen fibres and enlarged dentinal tubules. CONCLUSIONS The inward diffusion of LPS across DD differed from that of ID and the OF affected the inward diffusion of LPS. In the presence of the OF, the inward diffusion of LPS was reduced to near zero in both ID and DD. Nevertheless, when compared to that in the ID group, the OF produced the slightly greater effect to resist the inward LPS diffusion in the DD group.
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Kawanishi HN, Kawashima N, Suzuki N, Suda H, Takagi M. Effects of an inducible nitric oxide synthase inhibitor on experimentally induced rat pulpitis. Eur J Oral Sci 2004; 112:332-7. [PMID: 15279652 DOI: 10.1111/j.1600-0722.2004.00139.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nitric oxide (NO) is a biological effector molecule involved in a large variety of reactions and, as synthesized by inducible nitric oxide synthase (iNOS), has many important roles in inflammatory conditions. This study aimed to evaluate the anti-inflammatory effects of an iNOS-specific inhibitor, N-(3-(aminomethyl)benzyl)acetamidine (1400W), on experimentally induced rat pulpitis in the upper incisors of 6-wk-old male Wistar rats. 1400W (1 mg kg(-1)), the non-specific NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 50 mg kg(-1)), or sterile saline (control) were administered before the application of lipopolysaccharide (LPS). Rats were killed 3, 6, 9, 12, 24, 48, and 72 h after LPS application, and immunocompetent cells were detected immunohistochemically. The numbers of granulocytes infiltrating into the pulp were significantly depressed in the 1400W group compared with the saline and L-NAME groups. The kinetics of the macrophages and Ia(+) cells in the 1400W group were similar to those in the L-NAME group, while the maximum numbers in both groups were significantly reduced compared with those in the saline group. These results suggest that NO may be responsible for the infiltration of immunocompetent cells in the progress of pulpitis, and that 1400W is a promising candidate for controlling pulpal inflammatory reactions.
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Affiliation(s)
- Hiromi Nakano Kawanishi
- Pulp Biology and Endodontics, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan
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Coil J, Tam E, Waterfield JD. Proinflammatory cytokine profiles in pulp fibroblasts stimulated with lipopolysaccharide and methyl mercaptan. J Endod 2004; 30:88-91. [PMID: 14977303 DOI: 10.1097/00004770-200402000-00006] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pulpal disease is intimately associated with the immune system's response to bacteria products. Clinical pathology is mediated in part by the production of pyrogenic cytokines, especially interleukin (IL)-1, tumor necrosis factor (TNF)-alpha, and IL-6. Methyl mercaptan (CH3SH), a volatile sulfur compound produced by anaerobic Gram-negative bacteria, has been shown to contribute to the production of IL-1 by human mononuclear cells. In this report, we investigated the production of IL-1, TNF-alpha, and IL-6 by human pulp fibroblasts when stimulated for various periods of time with lipopolysaccharide (LPS) with or without the presence of CH3SH. We found that LPS and CH3SH had no effect on the production of IL-1 or TNF-alpha. However, LPS stimulated IL-6 production, and this production was augmented when CH3SH was present. We conclude that the volatile sulfur compound CH3SH plays a role in activation and modulation of the immune response through its role in production of IL-6.
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Affiliation(s)
- Jeffrey Coil
- Department of Oral, Biological, and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, Canada.
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40
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Esposito P, Varvara G, Murmura G, Terlizzi A, Caputi S. Ability of healthy and inflamed human dental pulp to reduce hydrogen peroxide. Eur J Oral Sci 2003; 111:454-6. [PMID: 12974692 DOI: 10.1034/j.1600-0722.2003.00062.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study examined the defensive ability of human dental pulp against H2O2 in healthy and reversible and irreversible pulpitis tissues through determination of catalase activity by spectrophotometric methods. Thirty-five systemically healthy patients were donors of the pulp tissue, and pulp conditions were assessed using clinical and X-ray evaluations. Catalase activity was 1.61 +/- 0.23 U mg(-1) protein in the healthy tissues, 2.99 +/- 0.45 U mg(-1) protein in the reversible pulpitis tissues, and 2.44 +/- 467 mU mg(-1) protein in the irreversible pulpitis tissues. All differences between the groups were statistically significant. These results point to a role for catalase during dental pulp inflammation in humans, and therefore demonstrate an inherent biological defense system against reactive oxidants in human dental pulp.
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Affiliation(s)
- Paola Esposito
- Department of Oral Sciences, Dental School, University G. D'Annunzio, Chieti, Italy
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41
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Esposito P, Varvara G, Caputi S, Perinetti G. Catalase activity in human healthy and inflamed dental pulps. Int Endod J 2003; 36:599-603. [PMID: 12950573 DOI: 10.1046/j.1365-2591.2003.00692.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To examine the catalase activity in clinically healthy and symptomatic human dental pulps to verify if an active defence system against oxidizing agents is present as a response to bacterial invasion. METHODOLOGY Thirty-three systemically healthy patients, 18 females and 15 males (ages: 11.0-25.9 years; mean 18.8 +/- 3.6), were the source of the pulp tissue. The condition of the pulps was assessed using clinical and radiographic evaluations. The specimens were recovered by longitudinally grooving and splitting the teeth (if extracted) or during endodontic treatment, and were matched for age and sex between the healthy and inflamed specimen groups. Catalase activity was determined through spectrophotometric methods. RESULTS Enzymatic activity was 1126 +/- 343 and 3074 +/- 698 mU mL(-1) x mg of total protein in the healthy and inflamed pulp tissue specimens, respectively. This difference was statistically significant (P<0.01). CONCLUSIONS These results indicate a role for catalase during dental pulp inflammation in humans, and may represent an inherent biological defence system against reactive oxidants of this tissue.
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Affiliation(s)
- P Esposito
- School of Dentistry, Department of Oral Sciences, Unit of Prosthetics, University G. D'Annunzio, Via dei Vestini, Chieti, Italy
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Botero TM, Mantellini MG, Song W, Hanks CT, Nör JE. Effect of lipopolysaccharides on vascular endothelial growth factor expression in mouse pulp cells and macrophages. Eur J Oral Sci 2003; 111:228-34. [PMID: 12786954 DOI: 10.1034/j.1600-0722.2003.00041.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Vascular endothelial growth factor (VEGF), a potent pro-angiogenic factor, might regulate the neovascularization observed in the pulp of teeth with deep caries. The purpose of this in vitro study was to evaluate the effect of bacterial lipopolysaccharides (LPS) on VEGF expression in dental pulp cells. Mouse odontoblast-like cells (MDPC-23) or undifferentiated pulp cells (OD-21) were exposed to 0-20 microg ml-1Escherichia coli LPS or 0-80 microg ml-1Prevotella intermedia LPS. As controls, mouse macrophages or gingival fibroblasts were exposed to LPS, since these cells are known to secrete VEGF. The VEGF expression was evaluated by reverse transcriptase polymerase chain reaction or enzyme-linked immunosorbent assay. The baseline expression levels of VEGF protein were higher in MDPC-23 and OD-21 than in fibroblasts or macrophages. Vascular endothelial growth factor protein expression was upregulated in MDPC-23 and macrophages exposed to E. coli LPS, but not in OD-21 cells or fibroblasts. Higher concentrations of P. intermedia LPS were required to induce VEGF expression in MDPC-23 cells. Treatment with LPS did not affect VEGF expression at the mRNA level in any of the cells evaluated. These results demonstrate that bacterial LPS upregulates VEGF expression in odontoblast-like cells and macrophages, and suggest that the regulation of VEGF expression occurs primarily at a post-transcriptional level.
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Affiliation(s)
- Tatiana M Botero
- Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, 1011 North University, Ann Arbor, MI 48109-1078, USA
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Yang YY, Tsai HF, Lu SC, Huang YF, Chang YC. Regulation of tissue inhibitors of metalloproteinase-1 gene expression by cytokines in human gingival fibroblasts. J Endod 2002; 28:803-5. [PMID: 12489647 DOI: 10.1097/00004770-200212000-00003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Tissue inhibitors of metalloproteinase (TIMP) are important participants in various physiological processes that involve tissues remodeling. They help maintain a delicate balance between physiological degradation and synthesis of the extracellular matrix. A better understanding of TIMP activity will be helpful in understanding the etiology of periapical lesions and their means of treatment. The fibroblast is a prominent cellular component of the periapical tissues. The potential implications of cytokine-mediated tissue destruction still remain to be elucidated. The purpose of this study was to determine the effects of interleukin (IL)-1alpha and transforming growth factor (TGF)-beta on the expressing of TIMP-1 by primary gingival fibroblast cultures. After exposure to cytokines for 8 h, total RNA in gingival fibroblasts was isolated and evaluated by reverse-transcriptase polymerase chain reaction. Densitometric analysis of the TIMP-1 mRNA gene expression, after normalization by beta-actin, demonstrated that exposure to IL-1alpha resulted in a decreased level of TIMP-1 mRNA compared with the control groups. However, the TIMP-1 mRNA was up-regulated by TGF-beta. In addition, when the cells were cultured in combination with TGF-beta (1 ng/ml) and IL-1alpha for 8 h, the level of TIMP-1 mRNA was dramatically reduced. These results demonstrated that in human periapical tissue cytokines differentially and specifically regulate expression of TIMP-1 mRNA. An understanding of the actions of cytokines on gingival fibroblasts may result in new therapies to augment current treatment of periapical lesions.
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Affiliation(s)
- Yu-Yen Yang
- Department of Medical Research, Show Chwan Memorial Hospital, Changhua, Taiwan
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Lu HX, Xiao MZ, Niu ZY, Guo XM, Zhao SL, Wang HG, Guo HY. Effect of IL-1ra on human dental pulp cells and pulpal inflammation. Int Endod J 2002; 35:807-11. [PMID: 12406373 DOI: 10.1046/j.1365-2591.2002.00542.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM This study was conducted to investigate the effect of interleukin-1 receptor antagonist (IL-1ra) on the LPS-induced interleukin-1beta (IL-1beta) synthesis in human dental pulp cells and to assess the role of IL-1ra in pulpal inflammation. METHODS IL-1beta from human dental pulp cells (HDP) was measured by sandwich ELISA; IL-1ra expression in pulpal tissue was detected by immunohistochemical staining. RESULTS Stimulation of HDP with increasing concentrations of FnLPS resulted in dose-dependent IL-1beta production. The addition of IL-1ra reduced FnLPS-induced IL-1beta synthesis in human dental pulp cells. Significant inhibition of the FnLPS-induced IL-1beta synthesis was observed when IL-1ra was added before treating with FnLPS for 60 min. Large numbers of IL-1ra positive neutrophils, plasmacytes, endothelial cells and lymphocytes were observed in inflamed pulp tissue. CONCLUSIONS IL-1ra could reduce LPS-stimulated IL-1beta synthesis, suggesting that IL-1ra may play a role in pulpitis.
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Affiliation(s)
- H-X Lu
- Department of Endodontics, College of Stomatology, Fourth Military Medical University, Xi'an, China.
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Chattipakorn SC, Sigurdsson A, Light AR, Narhi M, Maixner W. Trigeminal c-Fos expression and behavioral responses to pulpal inflammation in ferrets. Pain 2002; 99:61-9. [PMID: 12237184 DOI: 10.1016/s0304-3959(02)00054-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Injury to peripheral dental tissues evokes dynamic alternations in central sensory pathways. We have previously reported that transient stimulation of the dental pulp with noxious heat evokes the induction of the immediate early gene product Fos in the transitional region between subnucleus interpolaris and caudalis (Vi/Vc) and subnucleus caudalis (Vc). A question arises as to whether similar changes occur in response to inflammation to the tooth pulp. In this study, the effects of pulpal inflammation produced by bacterial lipopolysaccharide (LPS) on face-grooming behavior and trigeminal Fos expression were examined. Face-grooming behaviors were recorded daily for 3 days pre- and 24, 48 and 72 h post- LPS or saline application. All animals were perfused 72 h post- LPS or saline application. Brainstems were processed for Fos-like immunoreactivity (Fos-LI). Teeth were processed for H&E staining. Histological examination of LPS-treated teeth revealed features of an acute pulpitis. Moreover, LPS-treated animals showed greater face-grooming activity (i.e. tongue protrusions) directed to the injured tooth than the sham-operated group. The number of Fos-positive neurons was greater in the trigeminal subnucleus caudalis (Vc) and the transitional regions (Vi/Vc) in LPS-treated animals compared with sham-operated animals, and greater in the deeper laminae than the superficial laminae of each trigeminal region. LPS treatment did not evoke Fos expression in the rostral trigeminal regions above Vi/Vc. These results demonstrate that LPS-induced pulpal inflammation results in significant alterations in the Vi/Vc and Vc, and such changes may underlie the observed nociceptive behavioral responses and may play an important role in producing a symptomatic pulpitis in humans.
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Lin SK, Kuo MYP, Wang JS, Lee JJ, Wang CC, Huang S, Shun CT, Hong CY. Differential regulation of interleukin-6 and inducible cyclooxygenase gene expression by cytokines through prostaglandin-dependent and -independent mechanisms in human dental pulp fibroblasts. J Endod 2002; 28:197-201. [PMID: 12017180 DOI: 10.1097/00004770-200203000-00013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Increased levels of interleukin-1 (IL)-1, tumor necrosis factor-alpha (TNF-alpha), IL-6, and prostaglandin E2 (PGE2) have been detected in inflamed pulp tissue. To gain further insight into the molecular pathogenesis of pulpitis, we investigated the effects of IL-1alpha or TNF-alpha and PGE2, either alone or in combination on IL-6 and cyclooxygenase (COX)-2 messenger RNA (mRNA) production in cultured human dental pulp (HDP) fibroblasts. Exposure of HDP fibroblasts to IL-1alpha or TNF-alpha resulted in elevated levels of IL-6 (approximately 3.4 to approximately 10.4-fold) and COX-2 (approximately 5 to approximately 6.2-fold) mRNA. Simultaneous addition of IL-1alpha and PGE2 or TNF-alpha and PGE2 to the cultures significantly reduced the cytokine-induced IL-6 mRNA synthesis ranging from 45% to 65%. However, indomethacin enhanced the cytokine-stimulated IL-6 mRNA synthesis by approximately 1.7 to approximately 3.4-fold. This action could be reversed by exogenous PGE2. In contrast, PGE2 or indomethacin failed to modify the stimulatory effect of IL-1alpha or TNF-alpha on COX-2 gene expression. Because excessive levels of IL-6 and prostaglandins have been connected with the pathogenesis of several inflammatory diseases, our results suggest the involvement of HDP fibroblasts in the development of pulpitis via producing IL-6 and COX-2. Furthermore, expression of IL-6 and COX-2 genes in this cell seems to be differentially regulated by cytokines through prostaglandin-dependent and -independent pathways.
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Affiliation(s)
- Sze-Kwan Lin
- School of Dentistry, National Taiwan University, Taipei
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47
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Barkhordar RA, Ghani QP, Russell TR, Hussain MZ. Interleukin-1beta activity and collagen synthesis in human dental pulp fibroblasts. J Endod 2002; 28:157-9. [PMID: 12017170 DOI: 10.1097/00004770-200203000-00003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Immunopathologic reactions play a significant role in inflammatory diseases of dental pulp. Interleukin-1beta (IL-1beta) is recognized as a key player in mediating cellular immune response. In this study, we measured the content of IL-1beta and its effect on collagen synthesis in cultures of fibroblasts derived from healthy and diseased dental pulps. We found that diseased pulp fibroblasts contain 2.5-fold greater amounts of IL-1beta and synthesized 80% greater amounts of collagen compared with healthy pulp fibroblasts. However, exogenous IL-1beta failed to stimulate collagen synthesis by diseased fibroblasts, whereas collagen synthesis by healthy pulp fibroblasts was stimulated by more than 2-fold. These observations imply that pulp disease induces abnormalities associated with fibroblast response toward IL-1beta.
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Affiliation(s)
- Rahmat A Barkhordar
- Department of Preventive & Restorative Dental Sciences, School of Dentistry, University of California, San Francisco 94143, USA
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48
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Murakami Y, Hanazawa S, Tanaka S, Iwahashi H, Yamamoto Y, Fujisawa S. A possible mechanism of maxillofacial abscess formation: involvement of Porphyromonas endodontalis lipopolysaccharide via the expression of inflammatory cytokines. ORAL MICROBIOLOGY AND IMMUNOLOGY 2001; 16:321-5. [PMID: 11737653 DOI: 10.1034/j.1399-302x.2001.160601.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In a previous study, we developed a specific monoclonal antibody against Porphyromonas endodontalis lipopolysaccharide, and demonstrated that this lipopolysaccharide was detected in bacterially infected root canal fluid. We suggest here that P. endodontalis lipopolysaccharide in the infectious materials plays a stimulatory role in maxillofacial abscess formation via the expression of inflammatory cytokines. Our epidemiological study showed that this lipopolysaccharide was detected in significant levels the infectious material of patients with periapical periodontitis and odontogenic abscesses. Interestingly, infectious material-induced expression of tumor necrosis factor-alpha, interleukin-1beta, or neutrophil chemoattractant KC genes in mouse macrophages, was significantly neutralized by monoclonal antibody against the lipopolysaccharide. In addition, we also detected a significant amount of tumor necrosis factor-alpha in the infectious material. These results suggest that P. endodontalis lipopolysaccharide plays an important role in the pathogenic mechanism of maxillofacial abscess formation via the expression of inflammatory cytokines.
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Affiliation(s)
- Y Murakami
- Department of Oral Diagnosis, Meikai University School of Dentistry, 1-1 Keyakidai, Sakado City, Saitama 350-0283, Japan
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Rosen G, Shoshani M, Naor R, Sela MN. The purification and characterization of an 88-kDa Porphyromonas endodontalis 35406 protease. ORAL MICROBIOLOGY AND IMMUNOLOGY 2001; 16:326-31. [PMID: 11737654 DOI: 10.1034/j.1399-302x.2001.160602.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A Porphyromonas endodontalis ATCC 35406 protease was purified from Triton X-114 cell extracts by preparative SDS-PAGE followed by electroelution. The purified enzyme exhibits a molecular size of 88 kDa and was dissociated into two polypeptides of 43 and 41 kDa upon heating in the presence of sodium dodecyl sulfate with or without a reducing agent. The protease (pH optimum 7.5-8.0) degraded the extracellular matrix proteins fibrinogen and fibronectin. Collagen IV was also degraded at 37 degrees C but not at 28 degrees C. The protease also cleaved the bioactive peptide angiotensin at amino acid residue phenylalanine-8 and tyrosine-4 but failed to hydrolyze bradykinin, vasopressin and synthetic chromogenic substrates with phenylalanine or tyrosine at the P1 position. In addition, two peptidases were detected in P. endodontalis cells: a proline aminopeptidase that remained associated with the cell pellet after detergent extraction and peptidase/s that partitioned into the Triton X-114 phase after phase separation and degraded the bioactive peptides bradykinin and vasopressin. These P. endodontalis peptidases and proteases may play an important role in both the nutrition and pathogenicity of these assacharolytic microorganisms. The inactivation of bioactive peptides and degradation of extracellular matrix proteins by bacterial enzymes may contribute to the damage of host tissues accompanied with endodontic infections.
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Affiliation(s)
- G Rosen
- Department of Oral Biology, Faculty of Dental Medicine, Hebrew University, Hadassah Ein-Karem, 91120 Jerusalem, Israel
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Kuntz KA, Brown CE, Legan JJ, Kafrawy AH. An immunohistochemical study of osteoprotegerin in the human dental pulp. J Endod 2001; 27:666-9. [PMID: 11716077 DOI: 10.1097/00004770-200111000-00003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This study investigated the expression of osteoprotegerin (OPG) in healthy and inflamed dental pulps. Histological sections 7 microm thick of 47 teeth, either caries-free or affected by gross caries, were used. Sections were stained with hematoxylin-eosin, and other sections of the same specimen were subjected to the avidin-biotin peroxidase complex immunohistochemical procedure for detection of OPG. The study focused on the coronal pulp that was divided into peripheral and central regions. In the peripheral pulp healthy and inflamed specimens showed high OPG immunoreactivity of the odontoblastic layer. When no inflammation was present in the central pulp OPG immunoreactivity was light. Fibroblasts and endothelial cells showed immunoreactivity ranging from none to intense. When inflammation was present in the central pulp the chronic inflammatory cells showed intense immunoreactivity.
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Affiliation(s)
- K A Kuntz
- Department of Endodontics, Indiana University School of Dentistry, Indianapolis 46202-5186, USA
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