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Abraham D, Singh A, Goyal A. Symptomatic Irreversible Pulpitis Induces Increased Levels of Human NLRP3 in Gingival Crevicular Fluid Compared to Saliva: A Case Control Observational Study. J Endod 2023; 49:1480-1486. [PMID: 37634578 DOI: 10.1016/j.joen.2023.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 08/29/2023]
Abstract
INTRODUCTION The goal of this case-control observational study was to compare the levels of the human nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing-3 (NLRP3) protein in the saliva and gingival crevicular fluid (GCF) of patients with symptomatic irreversible pulpitis (SIP) and healthy controls. METHODS The 16 patients in the control group were matched with the 16 patients in the SIP group to create a total of 32 patients. In addition to saliva, GCF (n = 48) samples were collected from the involved tooth (n = 16), contralateral tooth (n = 16), and adjacent tooth (n = 16) in the SIP group. Saliva and GCF were taken from the healthy group as a baseline. An independent t-test was used for statistical analysis. The random-intercept model was used to compare the average NLRP3 levels in the SIP tooth, adjacent tooth, and contralateral tooth taking age as a covariate, and the P value was adjusted using Bonferroni correction. RESULTS There were significantly higher levels of NLRP3 in the saliva of SIP patients (1.78 ± 1.14 ng/ml) compared to the healthy control (0.70 ± 0.70 ng/ml) and in the GCF of the involved tooth (5.72 ± 0.63 ng/ml) compared to healthy people (1.60 ± 0.42 ng/ml) (P < .001). In SIP patients the mean difference of NLRP3 levels between SIP and contralateral teeth was significant at 4.13 ng/ml (95% confidence interval, 3.52-4.70 P < .001) and a mean difference between adjacent teeth and contralateral teeth was significant at 3.53 ng/ml [95% confidence interval, 2.94-4.12 P < .001]. The NLRP3 in GCF and saliva had a negative association in the affected tooth but a negligible correlation in healthy controls. CONCLUSION The NLRP3 inflammasome has the potential to be employed as a molecular diagnostic biomarker for pulpal disorders.
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Affiliation(s)
- Dax Abraham
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, School of Dental Sciences, MRIIRS, Faridabad, Haryana, India.
| | - Arundeep Singh
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, School of Dental Sciences, MRIIRS, Faridabad, Haryana, India
| | - Anjana Goyal
- Department of Biochemistry, Manav Rachna Dental College, School of Dental Sciences, MRIIRS, Faridabad, Haryana, India
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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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Shadab A, Mahjoor M, Abbasi-Kolli M, Afkhami H, Moeinian P, Safdarian AR. Divergent functions of NLRP3 inflammasomes in cancer: a review. Cell Commun Signal 2023; 21:232. [PMID: 37715239 PMCID: PMC10503066 DOI: 10.1186/s12964-023-01235-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/17/2023] [Indexed: 09/17/2023] Open
Abstract
The cancer is a serious health problem, which is The cancer death rate (cancer mortality) is 158.3 per 100,000 men and women per year (based on 2013-2017 deaths). Both clinical and translational studies have demonstrated that chronic inflammation is associated with Cancer progression. However, the precise mechanisms of inflammasome, and the pathways that mediate this phenomenon are not fully characterized. One of the most recently identified signaling pathways, whose activation seems to affect many metabolic disorders, is the "inflammasome" a multiprotein complex composed of NLRP3 (nucleotide-binding domain and leucine-rich repeat protein 3), ASC (apoptosis associated speck-like protein containing a CARD), and procaspase-1. NLRP3 inflammasome activation leads to the processing and secretion of the proinflammatory cytokines interleukin-1β (IL-1β) and IL-18. The goal of this paper is to review new insights on the effects of the NLRP3 inflammasome activation in the complex mechanisms of crosstalk between different organs, for a better understanding of the role of chronic inflammation in cancer pathogenesis. We will provide here a perspective on the current research on NLRP3 inflammasome, which may represent an innovative therapeutic target to reverse the malignancy condition consequences of the inflammation. Video Abstract.
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Affiliation(s)
- Alireza Shadab
- Department of Immunology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
- Iran University of Medical Sciences, Deputy of Health, Tehran, Iran
| | - Mohamad Mahjoor
- Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran
- Department of Immunology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Abbasi-Kolli
- Iran University of Medical Sciences, Deputy of Health, Tehran, Iran
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hamed Afkhami
- Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
- Department of Medical Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran
| | - Parisa Moeinian
- Department of Medical Genetics and Molecular Biology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amir-Reza Safdarian
- Immunology Board for Transplantation and Cell-Based Therapeutics (Immuno TACT), Universal Scientific Education and Research Network (USERN) Chicago, Chicago, IL, USA.
- Department of Immunology and Microbiology, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran.
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Leng S, Xu W, Wu L, Liu L, Du J, Yang F, Huang D, Zhang L. NLRP3 Disturbs Treg/Th17 Cell Balance to Aggravate Apical Periodontitis. J Dent Res 2023; 102:656-666. [PMID: 36883625 DOI: 10.1177/00220345231151692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
Apical periodontitis is an inflammatory condition that is considered an immunological reaction of the periapical tissue to invading bacteria and their pathogenic components. Recent research has revealed that NLR family pyrin domain containing 3 (NLRP3) is crucial to the pathogenesis of apical periodontitis and serves as a link between innate and adaptive immunity. The balance between regulatory T-cell (Treg) and T helper cell 17 (Th17 cell) determines the direction of the inflammatory response. Therefore, this study aimed to investigate whether NLRP3 exacerbated periapical inflammation by disturbing Treg/Th17 balance and the underlying regulatory mechanisms. In the present study, NLRP3 was raised in apical periodontitis tissues as opposed to healthy pulp tissues. Low NLRP3 expression in dendritic cells (DCs) increased transforming growth factor β secretion while decreasing interleukin (IL)-1β and IL-6 production. The Treg ratio and IL-10 secretion rose when CD4+ T cells were cocultured with DCs primed with IL-1β neutralizing antibody (anti-IL-1β) and specific small interfering RNA (siRNA) targeting NLRP3 (siRNA NLRP3), but the proportion of Th17 cells and IL-17 release dropped. Furthermore, siRNA NLRP3-mediated suppression of NLRP3 expression aided Treg differentiation and elevated Foxp3 expression as well as IL-10 production in CD4+ T cells. Inhibition of NLRP3 activity by MCC950 boosted the percentage of Tregs while decreasing the ratio of Th17 cells, leading to reduced periapical inflammation and bone resorption. Nigericin administration, however, exacerbated periapical inflammation and bone destruction with an unbalanced Treg/Th17 response. These findings demonstrate that NLRP3 is a pivotal regulator by regulating the release of inflammatory cytokines from DCs or directly suppressing Foxp3 expression to disturb Treg/Th17 balance, thus exacerbating apical periodontitis.
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Affiliation(s)
- S Leng
- Department of Operative Dentistry and Endodontics, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - W Xu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key laboratory of Oral Biomedical Research of Zhejiang Province Cancer Center of Zhejiang University, Hangzhou, China
| | - L Wu
- Department of Geriatric Stomatology, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - L Liu
- Department of Operative Dentistry and Endodontics, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - J Du
- Department of Health Care (Department of General Dentistry II), 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 & Shandong Provincial Clinical Research Center for Oral Diseases, Jinan, China
| | - F Yang
- Department of Operative Dentistry and Endodontics, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - D Huang
- Department of Operative Dentistry and Endodontics, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - L Zhang
- Department of Operative Dentistry and Endodontics, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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He H, Hao Y, Fan Y, Li B, Cheng L. The interaction between innate immunity and oral microbiota in oral diseases. Expert Rev Clin Immunol 2023; 19:405-415. [PMID: 36803467 DOI: 10.1080/1744666x.2023.2182291] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
INTRODUCTION Innate immunity serves as the frontline to combat invading pathogens. Oral microbiota is the total collection of microorganisms colonized within the oral cavity. By recognizing the resident microorganisms through pattern recognition receptors, innate immunity is capable of interacting with oral microbiota and maintaining homeostasis. Dysregulation of interaction may lead to the pathogenesis of several oral diseases. Decoding the crosstalk between oral microbiota and innate immunity may be contributory to developing novel therapies for preventing and treating oral diseases. AREAS COVERED This article reviewed pattern recognition receptors in the recognition of oral microbiota, the reciprocal interaction between innate immunity and oral microbiota, and discussed how the dysregulation of this relationship leads to the pathogenesis and development of oral diseases. EXPERT OPINION Many studies have been conducted to illustrate the relationship between oral microbiota and innate immunity and its role in the occurrence of different oral diseases. The impact and mechanisms of innate immune cells on oral microbiota and the mechanisms of dysbiotic microbiota in altering innate immunity are still needed to be investigated. Altering the oral microbiota might be a possible solution for treating and preventing oral diseases.
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Affiliation(s)
- Hongzhi He
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yu Hao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yu Fan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Bolei Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
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The protective role of curcumin in human dental pulp stem cells stimulated by lipopolysaccharide via inhibiting NF-κB p65 phosphorylation to suppress NLRP3 inflammasome activation. Clin Oral Investig 2023:10.1007/s00784-023-04885-8. [PMID: 36735089 DOI: 10.1007/s00784-023-04885-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 01/26/2023] [Indexed: 02/04/2023]
Abstract
OBJECTIVES This study aims to investigate the anti-inflammatory effect of curcumin and underlying mechanisms regarding the modulation of the nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome in human dental pulp stem cells (hDPSCs). MATERIALS AND METHODS The impact of curcumin on the viability of hDPSCs was evaluated. The effect of curcumin on the expression of IL-1β and NLRP3 in hDPSCs stimulated by lipopolysaccharide (LPS) was assessed. Then, LPS-primed hDPSCs were pre-treated with curcumin before ATP triggering NLRP3 inflammasome activation, and NLRP3 inflammasome-related mediators were assessed. The mechanism of curcumin inactivation of LPS plus ATP-induced inflammasome associated with NF-κB pathway was explored. The NF-κB pathway related pro-inflammatory mediators at mRNA and protein levels were evaluated. The expression of NF-κB p65 and phosphorylation p65 was visualized after curcumin or NF-κB inhibitor administrating respectively in hDPSCs with an activated NLRP3 inflammasome. Statistical analysis was performed. RESULTS While curcumin at the concentration of 0.5-5 μM showed no obvious impact on the viability of hDPSCs, it significantly decreased IL-1β and NLRP3 mRNA expression in LPS-induced hDPSCs in a dose-dependent manner. Curcumin significantly inhibited the LPS plus ATP-primed NLRP3 inflammasome activation in hDPSCs (NLRP3, ASC, caspase-1, and IL-1β). Curcumin evidently attenuated the LPS plus ATP-induced expression of NF-κB pathway-related pro-inflammatory mediators (IL-6, IL-8, TNF-α, and COX-2). Furthermore, curcumin effectively reduced p65 phosphorylation, which acts as an NF-κB inhibitor in hDPSCs with an activated NLRP3 inflammasome. CONCLUSIONS Curcumin pre-treatment may exert an anti-inflammatory role via inactivation of the NLRP3 inflammasome by inhibiting NF-κB p65 phosphorylation in cultured hDPSCs. CLINICAL RELEVANCE Curcumin may have therapeutic potential in pulp inflammation.
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Al Natour B, Lundy FT, About I, Jeanneau C, Dombrowski Y, El Karim IA. Regulation of caries-induced pulp inflammation by NLRP3 inflammasome: A laboratory-based investigation. Int Endod J 2023; 56:193-202. [PMID: 36287083 PMCID: PMC10099991 DOI: 10.1111/iej.13855] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 10/04/2022] [Accepted: 10/16/2022] [Indexed: 01/17/2023]
Abstract
AIM To evaluate the expression and function of the nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome in caries induced pulpitis. METHODOLOGY NLRP3 expression was determined with immunohistochemistry in the dental pulp and qPCR in dental pulp cells (DPCs). THP-1 macrophages expressing the apoptosis-related speck-like protein (ASC) and green fluorescent protein (GFP) fusion protein were used to assess NLRP3 inflammasome activation by live cell imaging, following treatment with lipopolysaccharide (LPS) and lipoteichoic acid (LTA). Caspase I inhibitor was used to confirm inflammasome activation. An ex-vivo pulpitis model in which the DPCs were co-cultured with THP-1 macrophages was used to study the effect of the NLRP3 inflammasome inhibitor (MCC950), and cytokines were measured using ELISA and multiplex array. Data were analysed using the t-test or anova followed by a Bonferroni post hoc test with the level of significance set at p ≤ .05. RESULTS NLRP3 inflammasome was differentially expressed in dental pulp of sound and carious teeth. Treatment of DPCs with LTA significantly upregulates NLRP3 and IL-1 β-expression (p < .05) and in induces more ASC specks formation compared to LPS. IL-β release in response to LTA treatment is significantly reduced with Caspase I inhibitor suggesting inflammasome dependent mechanism (p < .01). NLRP3-specific inhibitor, MCC950, significantly reduced IL-1β and IL-6 in an ex-vivo pulpitis model (p < .01) but had no effect on IL-8 or matrix metalloproteinase-9 (MMP-9). CONCLUSIONS Expression and upregulation of NLRP3 inflammasome with caries and LTA treatment suggest a role in caries-induced pulpitis. NLRP3 inhibitor attenuated the release of selective inflammatory cytokines and could be a potential treatment target that merit further investigation.
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Affiliation(s)
- Banan Al Natour
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.,Department of Oral Medicine and Surgery, Jordan University of Science and Technology, Irbid, Jordan
| | - Fionnuala T Lundy
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Imad About
- Aix Marseille University, CNRS, Institute of Movement Sciences, Marseille, France
| | - Charlotte Jeanneau
- Aix Marseille University, CNRS, Institute of Movement Sciences, Marseille, France
| | - Yvonne Dombrowski
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Ikhlas A El Karim
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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Álvarez-Vásquez JL, Castañeda-Alvarado CP. Dental pulp fibroblast: A star Cell. J Endod 2022; 48:1005-1019. [DOI: 10.1016/j.joen.2022.05.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 12/16/2022]
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Shaker ME. The contribution of sterile inflammation to the fatty liver disease and the potential therapies. Biomed Pharmacother 2022; 148:112789. [PMID: 35272137 DOI: 10.1016/j.biopha.2022.112789] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 11/02/2022] Open
Abstract
Hepatic inflammation is prevalent in several metabolic liver diseases. Recent scientific advances about the pathogenesis of metabolic liver diseases showed an emerging role of several damage-associated molecular patterns (DAMPs), including DNA, high-mobility group box 1 (HMGB1), ATP and uric acid. For these DAMPs to induce inflammation, they should stimulate pattern recognition receptors (PRRs), which are located in the hepatic immune cells like resident Kupffer cells, infiltrated neutrophils, monocytes or dendritic cells. As a consequence, proinflammatory cytokines like interleukins (ILs)-1β and 18 alongside tumor necrosis factor (TNF)-α are overproduced and released, leading to pronounced hepatic inflammation and cellular death. This review highlights the contribution of these DAMPs and PRRs in the settings of alcoholic and nonalcoholic steatohepatitis. The review also summarizes the therapeutic usefulness of targeting NLR family pyrin domain containing 3 (NLRP3)-inflammasome, Toll-like receptors (TLRs) 4 and 9, IL-1 receptor (IL-1R), caspase 1, uric acid and GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) in these hepatic inflammatory disorders.
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Affiliation(s)
- Mohamed E Shaker
- Department of Pharmacology, College of Pharmacy, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia.
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Nrf2 in the Field of Dentistry with Special Attention to NLRP3. Antioxidants (Basel) 2022; 11:antiox11010149. [PMID: 35052653 PMCID: PMC8772975 DOI: 10.3390/antiox11010149] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/06/2022] [Accepted: 01/09/2022] [Indexed: 02/06/2023] Open
Abstract
The aim of this review article was to summarize the functional implications of the nuclear factor E2-related factor or nuclear factor (erythroid-derived 2)-like 2 (Nrf2), with special attention to the NACHT (nucleotide-binding oligomerization), LRR (leucine-rich repeat), and PYD (pyrin domain) domains-containing protein 3 (NLRP3) inflammasome in the field of dentistry. NLRP3 plays a crucial role in the progression of inflammatory and adaptive immune responses throughout the body. It is already known that this inflammasome is a key regulator of several systemic diseases. The initiation and activation of NLRP3 starts with the oral microbiome and its association with the pathogenesis and progression of several oral diseases, including periodontitis, periapical periodontitis, and oral squamous cell carcinoma (OSCC). The possible role of the inflammasome in oral disease conditions may involve the aberrant regulation of various response mechanisms, not only in the mouth but in the whole body. Understanding the cellular and molecular biology of the NLRP3 inflammasome and its relationship to Nrf2 is necessary for the rationale when suggesting it as a potential therapeutic target for treatment and prevention of oral inflammatory and immunological disorders. In this review, we highlighted the current knowledge about NLRP3, its likely role in the pathogenesis of various inflammatory oral processes, and its crosstalk with Nrf2, which might offer future possibilities for disease prevention and targeted therapy in the field of dentistry and oral health.
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Xu G, Huang R, Xia W, Jiang B, Xiao G, Li Y. Associations between inflammasome-related gene NLRP3 Polymorphisms (rs10754558 and rs35829419) and risk of bladder cancer in a Chinese population. J Clin Lab Anal 2021; 35:e23973. [PMID: 34636069 PMCID: PMC8605168 DOI: 10.1002/jcla.23973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 06/21/2021] [Accepted: 07/08/2021] [Indexed: 12/24/2022] Open
Abstract
Background NLRP3 inflammasome as a component of immune system has been found related to several cancers, but no study has assessed NLRP3 polymorphisms on risk of bladder cancer (BC). We aim to investigate whether NLRP3 polymorphisms are associated with the risk and clinical features of bladder cancer (BC) in a Chinese population. Methods Genotype frequency of two commonly studied NLRP3 SNPs (rs10754558 and rs35829419) was examined in 154 patients with BC and the 308 healthy controls. NLRP3 gene polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism method. Results The distribution frequencies of GG, AG+GG, GG, and G allele in NLRP3 (rs10754558) genotypes were significantly different between case and control group (OR = 2.296, P = .022; OR = 1.598, P = .020; OR = 1.998, P = .049; OR = 1.557, P = .006), but no statistical difference existed for rs35829419. Among smokers and alcohol drinkers, for rs10754558, individuals with AG, GG, and GG+AG genotypes had a higher BC risk compared with individuals with AA; for rs35829419, individuals with variant genotypes (AG and GG+AG) had a stronger risk of developing BC compared with individuals with AA (all P < .05). In stratified analyses of tumor size and tumor node metastasis, AG or GG genotypes of rs10754558 and rs35829419 SNPs were associated with BC risk (both P < .05). Conclusion NLRP3 polymorphisms (rs10754558 and rs35829419) were related to BC risk and tumor size and lymph node metastasis, especially among smokers and alcohol drinkers.
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Affiliation(s)
- Gang Xu
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Ruohui Huang
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Wei Xia
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Bo Jiang
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Guancheng Xiao
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Yanmin Li
- Department of Urological Surgery, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
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Peng W, Zhang B, Sun Z, Zhang M, Guo L. Targeting the Nod-like receptor protein 3 Inflammasome with inhibitor MCC950 rescues lipopolysaccharide-induced inhibition of osteogenesis in Human periodontal ligament cells. Arch Oral Biol 2021; 131:105269. [PMID: 34601319 DOI: 10.1016/j.archoralbio.2021.105269] [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: 05/16/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 12/27/2022]
Abstract
OBJECTIVE We aim to investigate whether lipopolysaccharide-stimulated activition of Nod-like receptor protein 3 (NLRP3) Inflammasome inhibits osteogenesis in Human periodontal ligament cells (HPDLCs). Futhermore, to study whether MCC950 (a inhibitor of NLRP3 Inflammasome) rescues lipopolysaccharide-induced inhibition of osteogenesis in HPDLCs as well as the underlying mechanisms. METHODS HPDLCs were isolated from periodontal ligament of healthy orthodontic teeth from teenagers, and cells surface marker protein were detected by flow cytometry. Cells viability were determined by Cell Counting kit 8 assay. Enzyme-linked immunosorbent assay was used to analyze the secretion of proinflammatory factors. Western blot and real-time quantitative polymerase chain reaction (RT-qPCR) were measured assessing the expression of NLRP3 and Caspase-1. RT-qPCR, Alizarin red staining and Alkaline phosphatase staining were tested to determine the osteogenic differentiation capacity of HPDLCs. RESULTS It was found that lipopolysaccharide in the range of concentrations from 10 to 100 μg/ml significantly inhibited HPDLCs viability at 24 h and significantly improved proinflammatory cytokine expressions at 8 h and 24 h. MCC950 reversed lipopolysaccharide-stimulated proinflammatory cytokine expressions including interleukin-1β and interleukin-18, but not tumor necrosis factor-α. In addition, MCC950 rescued the lipopolysaccharide-inhibited osteogenic gene (Alkaline phosphatase, Runt-related transcription factor 2, and Osteocalcin). Moreover, MCC950 downregulated lipopolysaccharide-induced relative protein of NLRP3 Inflammasome signaling pathway, such as NLRP3 and Caspase-1. CONCLUSION MCC950 rescues lipopolysaccharide-induced inhibition of osteogenesis in HPDLCs via blocking NLRP3 Inflammasome signaling pathway, and it may be used as a promising therapeutic agent for periodontitis or periondontal regenerative related disease.
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Affiliation(s)
- Wei Peng
- Department of prosthodontics, Hospital of Stomatology Affiliated to Southwest Medical University, Luzhou, Sichuan, China.
| | - Bo Zhang
- Department of prosthodontics, Hospital of Stomatology Affiliated to Southwest Medical University, Luzhou, Sichuan, China.
| | - Zhengfan Sun
- Department of prosthodontics, Hospital of Stomatology Affiliated to Southwest Medical University, Luzhou, Sichuan, China.
| | - Meifeng Zhang
- Department of prosthodontics, Hospital of Stomatology Affiliated to Southwest Medical University, Luzhou, Sichuan, China.
| | - Ling Guo
- Department of prosthodontics, Hospital of Stomatology Affiliated to Southwest Medical University, Luzhou, Sichuan, China.
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13
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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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14
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Al Natour B, Lundy FT, Moynah PN, About I, Jeanneau C, Irwin CR, Domberoski Y, El Karim IA. Odontoblast cell death induces NLRP3 inflammasome-dependent sterile inflammation and regulates dental pulp cell migration, proliferation and differentiation. Int Endod J 2021; 54:941-950. [PMID: 33503274 DOI: 10.1111/iej.13483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 01/25/2021] [Indexed: 12/13/2022]
Abstract
AIM To investigate the ability of dead odontoblasts to initiate NLRP3 inflammasome-dependent sterile inflammation and to explore the effect on dental pulp cell (DPCs) migration, proliferation and odontogenic differentiation. METHODS Odontoblast-like cells were subjected to freezing-thawing cycles to produce odontoblast necrotic cell lysate (ONCL). DPCs were treated with ONCL to assess proliferation and migration. THP-1 differentiated macrophages stimulated with ONCL and live cell imaging and western blotting were used to assess NLRP3 inflammasome activation. Cytokines were measured with multiplex arrays and ELISA. qPCR, alkaline phosphatase and Alizarin red assays were used to assess odontogenic differentiation of DPCs. Data were analysed using the t-test or anova followed by a Bonferroni post hoc test with the level of significance set at P ≤ 0.05. RESULTS ONCL induced migration and proliferation of DPCs. Treatment of THP-1 macrophages with ONCL resulted in the release of the inflammatory cytokines IL-1β, IL-6, IL-8, TNFα, IFN-γ, CCL2 and angiogenic growth factors, angiogenin and angiopoietin. This inflammatory response was associated with activation of NFκB, p38MAPK and NLRP3 inflammasome. To confirm that ONCL induced inflammatory response is NLRP3 inflammasome-dependent, treatment with a caspase-1 inhibitor and a specific NLRP3 inhibitor significantly reduced IL-1β release in THP-1 macrophages (P = 0.01 and 0.001). Inflammasome activation product, IL-1β, induced odontogenic differentiation of DPCS as evident by the increase in odontogenic genes expression DMP-1, RUNX-2, DSPP and SPP, alkaline phosphatase activity and mineralization. CONCLUSION Dead odontoblasts induced NLRP3 inflammasome-dependent sterile inflammation and activated the migration, proliferation and differentiation of DPCs.
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Affiliation(s)
- B Al Natour
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.,Department of Oral Medicine and Oral Surgery, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan
| | - F T Lundy
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - P N Moynah
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.,Department of Biology, The Kathleen Lonsdale Institute for Human Health Research, National University of Ireland Maynooth, Maynooth, Ireland
| | - I About
- UMR 7287 CNRS, Faculté d'Odontologie, Université d'Aix-Marseille, Marseille, France
| | - C Jeanneau
- UMR 7287 CNRS, Faculté d'Odontologie, Université d'Aix-Marseille, Marseille, France
| | - C R Irwin
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Y Domberoski
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - I A El Karim
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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15
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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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16
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Wang D, Sun S, Xue Y, Qiu J, Ye T, Zhang R, Song B, He W, Zhang Y, Jiang W. MicroRNA-223 negatively regulates LPS-induced inflammatory responses by targeting NLRP3 in human dental pulp fibroblasts. Int Endod J 2020; 54:241-254. [PMID: 32966618 DOI: 10.1111/iej.13413] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/08/2020] [Accepted: 09/14/2020] [Indexed: 12/11/2022]
Abstract
AIM To investigate the effect of miR-223 on NLRP3, subsequently regulating the production of the NLRP3/CASP1 inflammasome pathway-mediated proinflammatory cytokines IL-1β and IL-18 in human dental pulp fibroblasts (HDPFs). METHODOLOGY Human dental pulp tissue (HDPT) and HDPFs were obtained from impacted third molars. The miR-223 mimics and inhibitor or NLRP3 plasmid were used to upregulate or downregulate miR-223 or NLRP3 in HDPFs, respectively. Computational prediction via TargetScan 5.1 and a luciferase reporter assay was conducted to confirm target association. The mRNA and protein expression of NLRP3, caspase-1, IL-1β and IL-18 was determined by qRT-PCR and Western blotting, respectively. The release of IL-1β and IL-18 was analysed by ELISA. The significance of the differences between the experimental and the control groups was determined using one-way analysis of variance; P < 0.05 indicated statistical significance. RESULTS A decrease in miR-223 and an increase in NLRP3 in HDPT occurred during the transformation of reversible pulpitis into irreversible pulpitis compared to that in healthy pulp tissue (P < 0.05). The computational prediction and luciferase reporter assay confirmed that NLRP3 was a direct target of miR-223 in HDPFs. The miR-223 inhibitor further promoted ATP plus LPS-induced NLRP3/CASP1 inflammasome pathway activation compared to the ATP plus LPS-induced group (P < 0.05). In contrast, the miR-223 mimic significantly inhibited the NLRP3/CASP1 inflammasome pathway activation induced by ATP plus LPS compared to the ATP plus LPS-induced group (P < 0.05). CONCLUSION MiR-223 served as a negative regulator involved in the control of the production and secretion of proinflammatory cytokines mediated by the NLRP3/CASP1 inflammasome pathway by targeting NLRP3. These data provide insight into the potential regulatory effects of miRNAs on the NLRP3 inflammasome, thus opening up novel potential therapeutic avenues for future endodontic treatment.
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Affiliation(s)
- D Wang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China.,Department of Occupational and Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an, China
| | - S Sun
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of Stomatology, Fourth Military Medical University, Xi'an, China
| | - Y Xue
- Department of Occupational and Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an, China
| | - J Qiu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China
| | - T Ye
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China
| | - R Zhang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China.,Department of Stomatology, First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - B Song
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China.,School of Dentistry, College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK
| | - W He
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China
| | - Y Zhang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China
| | - W Jiang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China.,School of Dentistry, College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK
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17
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Regulated Cell Death in Pulpitis. J Endod 2020; 46:1403-1413. [DOI: 10.1016/j.joen.2020.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/25/2020] [Accepted: 07/04/2020] [Indexed: 12/27/2022]
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18
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Expression of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 6 in human dental pulp tissues and cells. Arch Oral Biol 2020; 117:104794. [DOI: 10.1016/j.archoralbio.2020.104794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 05/29/2020] [Accepted: 05/31/2020] [Indexed: 01/27/2023]
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19
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Hong H, Chen X, Li K, Wang N, Li M, Yang B, Yu X, Wei X. Dental follicle stem cells rescue the regenerative capacity of inflamed rat dental pulp through a paracrine pathway. Stem Cell Res Ther 2020; 11:333. [PMID: 32746910 PMCID: PMC7397608 DOI: 10.1186/s13287-020-01841-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/27/2020] [Accepted: 07/17/2020] [Indexed: 02/07/2023] Open
Abstract
Background Pulpitis is a common dental disease characterized by sustained inflammation and impaired pulp self-repair. Mesenchymal stem cell-based minimally invasive vital pulp therapy (MSC-miVPT) is a potential treatment method, but its application is limited by the difficulty in acquiring MSCs. We recently revealed the immunomodulatory effects of rat dental follicle stem cells (rDFSCs) on acute lung injury. The present study focused on the paracrine effects of rDFSCs on the inflammation and regeneration of rat injured dental pulp to detect whether DFSCs are a potential candidate for MSC-miVPT. Methods Conditioned medium from rDFSCs (rDFSC-CM) was applied to lipopolysaccharide (LPS)-induced inflammatory rat dental pulp cells (rDPCs). The inflammation and regeneration of rDPCs were detected by RT-qPCR, Western blotting, immunofluorescence staining, Cell Counting Kit-8 (CCK-8) assay, flow cytometry, wound-healing assay, and Masson’s staining. The effects of rDFSC-CM on inflamed rat dental pulp were further evaluated by hematoxylin-eosin and immunohistochemical staining. Results rDFSC-CM downregulated the ERK1/2 and NF-κB signaling pathways, which resulted in suppression of the expression of IL-1β, IL-6, and TNF-α and promotion of the expression of IL-4 and TGF-β, and these findings lead to the attenuation of rDPC inflammation. rDFSC-CM enhanced the in vitro proliferation, migration, and odontogenic differentiation of inflammatory rDPCs and their in vivo ectopic dentinogenesis. Furthermore, rDFSC-CM inhibited inflammatory cell infiltration in rat pulpitis and triggered Runx2 expression in some of the odontoblast-like cells surrounding the injured site, and these effects were conducive to the repair of inflamed dental pulp. Conclusions rDFSC-CM exhibits therapeutic potential by rescuing the regeneration of the inflamed rat dental pulp through an immunomodulatory mechanism, indicating the application prospects of DFSCs in biological regenerative endodontics.
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Affiliation(s)
- Hong Hong
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, People's Republic of China
| | - Xiaochuan Chen
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, People's Republic of China.,Department of Stomatology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, People's Republic of China
| | - Kun Li
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, People's Republic of China
| | - Nan Wang
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, People's Republic of China
| | - Mengjie Li
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, People's Republic of China
| | - Bo Yang
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, People's Republic of China
| | - Xiaoqi Yu
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, People's Republic of China.
| | - Xi Wei
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, People's Republic of China.
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20
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Fawzy El-Sayed KM, Elsalawy R, Ibrahim N, Gadalla M, Albargasy H, Zahra N, Mokhtar S, El Nahhas N, El Kaliouby Y, Dörfer CE. The Dental Pulp Stem/Progenitor Cells-Mediated Inflammatory-Regenerative Axis. TISSUE ENGINEERING PART B-REVIEWS 2019; 25:445-460. [DOI: 10.1089/ten.teb.2019.0106] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Karim M. Fawzy El-Sayed
- Oral Medicine and Periodontology Department, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt
- Clinic for Conservative Dentistry and Periodontology, School of Dental Medicine, Christian Albrechts University, Kiel, Germany
| | | | | | | | | | - Nehal Zahra
- Faculty of Dentistry, New Giza University, Giza, Egypt
| | | | | | | | - Christof E. Dörfer
- Clinic for Conservative Dentistry and Periodontology, School of Dental Medicine, Christian Albrechts University, Kiel, Germany
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21
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Lv K, Wang G, Shen C, Zhang X, Yao H. Role and mechanism of the nod-like receptor family pyrin domain-containing 3 inflammasome in oral disease. Arch Oral Biol 2018; 97:1-11. [PMID: 30315987 DOI: 10.1016/j.archoralbio.2018.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 10/02/2018] [Accepted: 10/03/2018] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To summarize evidence and data from experimental studies regarding the role and mechanism of the Nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome in the pathogenesis of several representative oral diseases. MATERIALS AND METHODS A literature search of PubMed and EBSCO was performed. The literature was searched using a combination of keywords, e.g., NLRP3 inflammasome, inflammation, microorganisms, oral inflammatory diseases, and oral immunological diseases. RESULTS The initiation and activation of the NLRP3 inflammasome are associated with the pathogenesis and progression of several representative oral diseases, including periodontitis, oral lichen planus, dental pulp disease, and oral cavity squamous cell carcinoma. CONCLUSIONS The NLRP3 inflammasome plays a crucial role in the progression of inflammatory and adaptive immune responses. The possible role of the NLRP3 inflammasome in several oral diseases, including not only periodontitis and pulpitis but also mucosal diseases and oral cavity squamous cell carcinoma, may involve the aberrant regulation of inflammatory and immune responses. Understanding the cellular and molecular biology of the NLRP3 inflammasome is necessary because the NLRP3 inflammasome may be a potential therapeutic target for the treatment and prevention of oral inflammatory and immunological diseases.
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Affiliation(s)
- Kejia Lv
- Department of Stomatology, First Affiliated Hospital, College of Medicine, Zhejiang University, China
| | - Guohua Wang
- Department of Stomatology, First Affiliated Hospital, College of Medicine, Zhejiang University, China
| | - Chenlu Shen
- Department of Stomatology, First Affiliated Hospital, College of Medicine, Zhejiang University, China
| | - Xia Zhang
- Department of Stomatology, Affiliated Yinzhou People Hospital, College of Medicine, Ningbo University, China
| | - Hua Yao
- Department of Stomatology, First Affiliated Hospital, College of Medicine, Zhejiang University, China.
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22
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Cooper PR, Chicca IJ, Holder MJ, Milward MR. Inflammation and Regeneration in the Dentin-pulp Complex: Net Gain or Net Loss? J Endod 2018; 43:S87-S94. [PMID: 28844308 DOI: 10.1016/j.joen.2017.06.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The balance between the immune/inflammatory and regenerative responses in the diseased pulp is central to the clinical outcome, and this response is unique within the body because of its tissue site. Cariogenic bacteria invade the dentin and pulp tissues, triggering molecular and cellular events dependent on the disease stage. At the early onset, odontoblasts respond to bacterial components in an attempt to protect the tooth's hard and soft tissues and limit disease progression. However, as disease advances, the odontoblasts die, and cells central to the pulp core, including resident immune cells, pulpal fibroblasts, endothelial cells, and stem cells, respond to the bacterial challenge via their expression of a range of pattern recognition receptors that identify pathogen-associated molecular patterns. Subsequently, recruitment and activation occurs of a range of immune cell types, including neutrophils, macrophages, and T and B cells, which are attracted to the diseased site by cytokine/chemokine chemotactic gradients initially generated by resident pulpal cells. Although these cells aim to disinfect the tooth, their extravasation, migration, and antibacterial activity (eg, release of reactive oxygen species [ROS]) along with the bacterial toxins cause pulp damage and impede tissue regeneration processes. Recently, a novel bacterial killing mechanism termed neutrophil extracellular traps (NETs) has also been described that uses ROS signaling and results in cellular DNA extrusion. The NETs are decorated with antimicrobial peptides (AMPs), and their interaction with bacteria results in microbial entrapment and death. Recent data show that NETs can be stimulated by bacteria associated with endodontic infections, and they may be present in inflamed pulp tissue. Interestingly, some bacteria associated with pulpal infections express deoxyribonuclease enzymes, which may enable their evasion of NETs. Furthermore, although NETs aim to localize and kill invading bacteria using AMPs and histones, limiting the spread of the infection, data also indicate that NETs can exacerbate inflammation and their components are cytotoxic. This review considers the potential role of NETs within pulpal infections and how these structures may influence the pulp's vitality and regenerative responses.
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Affiliation(s)
- Paul R Cooper
- Oral Biology, School of Dentistry, College of Medical and Dental Sciences, Edgbaston, Birmingham, UK.
| | - Ilaria J Chicca
- Oral Biology, School of Dentistry, College of Medical and Dental Sciences, Edgbaston, Birmingham, UK
| | - Michael J Holder
- Oral Biology, School of Dentistry, College of Medical and Dental Sciences, Edgbaston, Birmingham, UK
| | - Michael R Milward
- Oral Biology, School of Dentistry, College of Medical and Dental Sciences, Edgbaston, Birmingham, UK
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23
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Yumoto H, Hirao K, Hosokawa Y, Kuramoto H, Takegawa D, Nakanishi T, Matsuo T. The roles of odontoblasts in dental pulp innate immunity. JAPANESE DENTAL SCIENCE REVIEW 2018; 54:105-117. [PMID: 30128058 PMCID: PMC6094490 DOI: 10.1016/j.jdsr.2018.03.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 02/06/2018] [Accepted: 03/01/2018] [Indexed: 11/26/2022] Open
Abstract
Odontoblasts located in the outermost layer of dental pulp form a natural barrier between mineralized tissues, dentin, and soft tissues, dental pulp, of the vital tooth, and they first recognize caries-related pathogens and sense external irritations. Therefore, odontoblasts possess a specialized innate immune system to fight oral pathogens invading into dentin. Generally, the rapid initial sensing of microbial pathogens, especially pathogen-associated molecular patterns (PAMPs) shared by microorganisms, are mediated by pattern recognition receptors (PRRs), such as Toll-like receptor and the nucleotide-binding oligomerization domain (NOD). The innate immune responses in odontoblasts initiated by sensing oral pathogens provide host protective events, such as inflammatory reactions, to produce a variety of pro-inflammatory mediators, including chemokines and cytokines. These attract various inflammatory cells and cause antibacterial reactions, such as the production of defensins, to kill microorganisms in the proximal region of the odontoblast layer. This review focuses on innate immunity, especially cellular and molecular mechanisms regarding the sensing of PAMPs from oral pathogens by PRRs, in odontoblasts and provides information for future studies for the development of novel therapeutic strategies, including diagnosis and treatment, to prevent exceeding dental pulp inflammation and preserve the dental pulp tissues.
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Affiliation(s)
- Hiromichi Yumoto
- Department of Periodontology and Endodontology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Kouji Hirao
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Yuki Hosokawa
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Hitomi Kuramoto
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Daisuke Takegawa
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Tadashi Nakanishi
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
| | - Takashi Matsuo
- Department of Conservative Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan
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Huang S, Song Z, Huang Q, Jiang L, Chen L, Wang R, Lin Z. AIM2 Inflammasome Is Critical for dsDNA-Induced IL-1β Secretion in Human Dental Pulp Cells. Inflammation 2017; 41:409-417. [DOI: 10.1007/s10753-017-0697-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Lu WL, Song DZ, Yue JL, Wang TT, Zhou XD, Zhang P, Zhang L, Huang DM. NLRP3 inflammasome may regulate inflammatory response of human periodontal ligament fibroblasts in an apoptosis-associated speck-like protein containing a CARD (ASC)-dependent manner. Int Endod J 2017; 50:967-975. [PMID: 27864974 DOI: 10.1111/iej.12722] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 11/14/2016] [Indexed: 02/05/2023]
Affiliation(s)
- W. L. Lu
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - D. Z. Song
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - J. L. Yue
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - T. T. Wang
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - X. D. Zhou
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - P. Zhang
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - L. Zhang
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - D. M. Huang
- Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Conservative Dentistry; West China Hospital of Stomatology; Sichuan University; Chengdu China
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Song Z, Chen L, Guo J, Qin W, Wang R, Huang S, Yang X, Tian Y, Lin Z. The Role of Transient Receptor Potential Cation Channel, Subfamily C, Member 1 in the Odontoblast-like Differentiation of Human Dental Pulp Cells. J Endod 2016; 43:315-320. [PMID: 28041683 DOI: 10.1016/j.joen.2016.10.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Revised: 09/20/2016] [Accepted: 10/11/2016] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Calcium ions (Ca2+) actively participate in reparative dentin formation by promoting cellular proliferation and differentiation of human dental pulp cells (hDPCs). Transient receptor potential cation channel, subfamily C, member 1 (TRPC1) activates Ca2+ entry upon store depletion in a variety of cell types. However, the function of TRPC1 in hDPCs has not been reported. Therefore, we aimed to analyze the role of TRPC1 in hDPCs undergoing odontoblast-like differentiation. METHODS Immunohistochemical staining was used to determine the distribution of TRPC1 in pulp tissues. Western blot analysis was used to detect the protein level of TRPC1 in the odontoblast-like differentiation of hDPCs. Knockdown of TRPC1 was performed with an adenoviral vector to evaluate the role of TRPC1 in hDPCs during odontoblast-like differentiation. RESULTS The results showed that TRPC1 was highly expressed in the cytoplasm of dental pulp cells, especially in the odontoblast layer of the healthy pulp. Moreover, the protein level of TRPC1 increased in a time-dependent manner during the odontoblast-like differentiation of hDPCs. Importantly, knockdown of TRPC1 attenuated the process of odontoblast-like differentiation as indicated by the reduction in mineralized nodules and the down-regulation of dentin sialophosphoprotein and dentin matrix protein 1. Moreover, knockdown of TRPC1 decreased Ca2+ entry to the cytoplasm of hDPCs. CONCLUSIONS Our data indicated a pivotal role of TRPC1 in the odontoblastlike differentiation of hDPCs, which may be a therapeutic target to enhance reparative dentin formation.
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Affiliation(s)
- Zhi Song
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Lingling Chen
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Jia Guo
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Wei Qin
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Runfu Wang
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Shuheng Huang
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Xiaoting Yang
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China
| | - Yaguang Tian
- Department of Stomatology, Hainan General Hospital, Haikou, Hainan, China.
| | - Zhengmei Lin
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China.
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Absent in melanoma 2 (AIM2) expressed in human dental pulp mediates IL-1β secretion in response to cytoplasmic DNA. Inflammation 2015; 38:566-75. [PMID: 24986444 DOI: 10.1007/s10753-014-9963-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The inflammasome has been determined to play an important role in inflammatory diseases in recent years. Absent in melanoma 2 (AIM2), an inflammasome that recognizes cytoplasmic DNA, has recently been identified as a critical regulator of immune responses. In this study, we explored whether AIM2 was expressed in human dental pulp and defined the role of AIM2 in regulating interleukin (IL)-1β secretion. We demonstrated that AIM2 was only detected in the odontoblast layer of healthy dental pulp, whereas strong expression was observed in inflamed dental pulp. Stimulation with interferon gamma (IFN-γ) and cytoplasmic DNA significantly activated the AIM2 inflammasome and increased IL-1β secretion in human dental pulp cells (HDPCs) in a time- and dose-dependent manner. Moreover, the knockdown of AIM2 downregulated both cleaved-caspase-1 expression and IL-1β release in HDPCs. These results suggest that AIM2 expressed in human dental pulp plays an important role in the immune defense by activating the inflammasome signaling pathway.
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An Overview of Pathogen Recognition Receptors for Innate Immunity in Dental Pulp. Mediators Inflamm 2015; 2015:794143. [PMID: 26576076 PMCID: PMC4630409 DOI: 10.1155/2015/794143] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/28/2015] [Indexed: 12/16/2022] Open
Abstract
Pathogen recognition receptors (PRRs) are a class of germ line-encoded receptors that recognize pathogen-associated molecular patterns (PAMPs). The activation of PRRs is crucial for the initiation of innate immunity, which plays a key role in first-line defense until more specific adaptive immunity is developed. PRRs differ in the signaling cascades and host responses activated by their engagement and in their tissue distribution. Currently identified PRR families are the Toll-like receptors (TLRs), the C-type lectin receptors (CLRs), the nucleotide-binding oligomerization domain-like receptors (NLRs), the retinoic acid-inducible gene-I-like receptors (RLRs), and the AIM2-like receptor (ALR). The environment of the dental pulp is substantially different from that of other tissues of the body. Dental pulp resides in a low compliance root canal system that limits the expansion of pulpal tissues during inflammatory processes. An understanding of the PRRs in dental pulp is important for immunomodulation and hence for developing therapeutic targets in the field of endodontics. Here we comprehensively review recent finding on the PRRs and the mechanisms by which innate immunity is activated. We focus on the PRRs expressed on dental pulp and periapical tissues and their role in dental pulp inflammation.
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Zhang A, Wang P, Ma X, Yin X, Li J, Wang H, Jiang W, Jia Q, Ni L. Mechanisms that lead to the regulation of NLRP3 inflammasome expression and activation in human dental pulp fibroblasts. Mol Immunol 2015; 66:253-62. [PMID: 25863775 DOI: 10.1016/j.molimm.2015.03.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/16/2015] [Accepted: 03/09/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND The NLRP3 inflammasome plays an important role in the cellular defense against invading pathogens and is reported to be expressed in human dental pulp fibroblasts (HDPFs). However, the role of the NLRP3 inflammasome in HDPFs during pulpal infection and inflammation remains unclear. OBJECTIVES To elucidate the function of the NLRP3 inflammasome and the mechanisms that lead to its expression and activation in HDPFs. METHODS The test model used lipopolysaccharide (LPS) and adenosine triphosphate (ATP) to simulate an inflammatory environment. Lentiviral vectors encoding short hairpin RNAs were used to knock down NLRP3 and caspase-1 in HDPFs. Specific inhibitors were used to determine whether the toll-like receptor 4 (TLR4), myeloid differentiating factor 88 (MyD88), or nuclear factor-kappa B (NF-κB) pathways were involved in the regulation of NLRP3 expression. Reactive oxygen species (ROS) production was measured by fluorescent microscopy and flow cytometry using the total ROS/superoxide detection kit. Gene and protein expression were quantified by real-time polymerase chain reaction and Western blot, while cytokine release was measured by an enzyme-linked immunosorbent assay. RESULTS LPS up-regulated NLRP3 and IL-1β expression while ATP induced the activation of caspase-1 and the release of IL-1β in LPS-primed HDPFs. The knockdown of NLRP3 or caspase-1 expression significantly inhibited IL-1β secretion. Pretreatment with a TLR4 inhibitor, a MyD88 inhibitory peptide, or an I Kappa B alpha (IκBα) phosphorylation inhibitor significantly inhibited LPS-induced NLRP3 and IL-1β expression. ATP potently promoted ROS generation in HDPFs; N-acetyl cysteine inhibited ROS production, caspase-1 activation and IL-1β secretion induced by ATP. CONCLUSIONS Our results demonstrated that the NLRP3 inflammasome in HDPFs is crucial for IL-1β secretion in response to LPS plus ATP. LPS engaged the TLR4/MyD88/NF-κB pathway to enhance NLRP3 and pro-IL-1β expression in HDPFs. ATP promoted the generation of ROS and activated the NLRP3 inflammasome in a ROS-dependent manner.
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Affiliation(s)
- Ansheng Zhang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Peina Wang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Xiaoying Ma
- Out-patient Department, The 323 Hospital of PLA, Xi'an 710054, Shaanxi, China
| | - Xiao Yin
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Jiguo Li
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Haijing Wang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Wenkai Jiang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Qian Jia
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China
| | - Longxing Ni
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 145 Changle West Road, Xi'an 710032, Shaanxi, China.
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Jiang W, Lv H, Wang H, Wang D, Sun S, Jia Q, Wang P, Song B, Ni L. Activation of the NLRP3/caspase-1 inflammasome in human dental pulp tissue and human dental pulp fibroblasts. Cell Tissue Res 2015; 361:541-55. [PMID: 25684031 PMCID: PMC4529451 DOI: 10.1007/s00441-015-2118-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 01/07/2015] [Indexed: 12/21/2022]
Abstract
The NLRP3/caspase-1 inflammasome pathway plays an important role in cellular immune defence against bacterial infection; however, its function in human dental pulp tissue and human dental pulp fibroblasts remains poorly understood. We demonstrate that NLRP3 protein expression occurs to a greater extent in pulp tissue with irreversible pulpitis than in normal pulp tissue and in tissue with reversible pulpitis. Caspase-1 is present in its active (cleaved) form only in pulp tissue with irreversible pulpitis. NLRP3 and caspase-1 are expressed in the odontoblast layers in normal human dental pulp tissue, whereas in inflamed pulp tissue, the odontoblast layers are disrupted and dental pulp cells are positive for NLRP3 and caspase-1. Additionally, we investigate the role of the NLRP3/caspase-1 inflammasome pathway in human dental pulp fibroblasts and show that ATP activates the P2X7 receptor on the cell membrane triggering K(+) efflux and inducing the gradual recruitment of the membrane pore pannexin-1. Extracellular lipopolysaccharide is able to penetrate the cytosol and activate NLRP3. Furthermore, the low intracellular K(+) concentration in the cytosol triggers reactive oxygen species generation, which also induces the NLRP3 inflammasome. Thus, the NLRP3/caspase-1 pathway has a biological role in the innate immune response mounted by human dental pulp fibroblasts.
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Affiliation(s)
- Wenkai Jiang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Haipeng Lv
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Haijing Wang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Diya Wang
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi’an, People’s Republic of China
| | - Shukai Sun
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Qian Jia
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Peina Wang
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
| | - Bing Song
- Tissue Engineering and Regenerative Dentistry, School of Dentistry, Cardiff University, Heath Park, Cardiff, CF14 4XY UK
| | - Longxing Ni
- State Key Laboratory of Military Stomatology, Department of Operative Dentistry & Endodontics, School of Stomatology, The Fourth Military Medical University, 710032 Shaanxi, People’s Republic of China
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RETRACTED: Unique proliferation response in odontoblastic cells derived from human skeletal muscle stem cells by cytokine-induced matrix metalloproteinase-3. Exp Cell Res 2015; 331:105-114. [DOI: 10.1016/j.yexcr.2014.09.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/05/2014] [Accepted: 09/11/2014] [Indexed: 11/18/2022]
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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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Ozeki N, Yamaguchi H, Kawai R, Hiyama T, Nakata K, Mogi M, Nakamura H. Cytokines induce MMP-3-regulated proliferation of embryonic stem cell-derived odontoblast-like cells. Oral Dis 2014; 20:505-13. [PMID: 23902456 DOI: 10.1111/odi.12165] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 07/05/2013] [Accepted: 07/09/2013] [Indexed: 12/22/2022]
Abstract
OBJECTIVES Matrix metalloproteinase (MMP)-3 expression increases after pulpectomy and accelerates angiogenesis in rat dental pulp by an uncharacterised mechanism. Odontoblasts, a major component of dental pulp, could represent a therapeutic target. We investigated whether MMP-3 activity is induced by cytokines and/or is associated with cell proliferation and apoptosis in embryonic stem cell-derived odontoblast-like cells. MATERIALS AND METHODS We used reverse transcriptase polymerase chain reaction, western blotting, an MMP-3 activity assay, a BrdU-cell proliferation enzyme-linked immunosorbent assay and DNA fragmentation analysis to evaluate siRNA-mediated downregulation of MMP-3 expression and activity, and any changes in the proliferative and apoptotic responses associated with this reduced expression. RESULTS Pro-inflammatory cytokines (interleukin-1β, tumour necrosis factor-α and interferon-γ, at relatively low concentrations) induced MMP-3 mRNA and protein expression, and increased MMP-3 activity and cell proliferation, but not apoptosis. MMP-3 silencing produced a potent and significant suppression of cytokine-induced MMP-3 expression and activity, decreased cell proliferation and increased apoptosis. These effects were rescued by application of exogenous MMP-3. CONCLUSIONS Our results suggest that pro-inflammatory cytokines induce MMP-3-regulated cell proliferation and anti-apoptosis effects in odontoblast-like cells derived from embryonic stem cells, in addition to their well-documented destructive role in inflammation.
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Affiliation(s)
- N Ozeki
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
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Liu S, Li Q, Liu Y. Immunohistochemical localization of NALP3 inflammasome in experimental periapical lesions. Int Endod J 2014; 47:949-57. [PMID: 24386947 DOI: 10.1111/iej.12240] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 01/01/2014] [Indexed: 02/07/2023]
Abstract
AIM To explore the role of NALP3 inflammasome [NALP3, its effector molecule apoptosis associated speck-like protein (ASC), caspase-1, interleukin (IL)-1β and IL-18] in the development of periapical lesions in rats. METHODOLOGY Periapical lesions were developed within 21 days after mandibular first molar pulp exposure in Sprague-Dawley rats. The animals were randomly sacrificed at 0, 1, 3, 7, 10, 14 and 21 days after pulpal exposure. The bilateral mandibles were extracted for histological processing, then they were haematoxylin-eosin (HE) stained to examine inflammation infiltration in the apical region and immunohistochemically examined for the NALP3 inflammasome signalling pathway. Data were analysed by one-way analysis of variance and the Pearson(') s correlation and linear tendency test. RESULTS NALP3 was detected in the cytoplasm of fibroblasts, monocytes, neutrophils, macrophages and vascular endothelial cells in the periapical region. From day 1 to day 21, the number of NALP3-positive cells ascended and was significantly correlated with the intensity of inflammatory infiltration (r = 0.776, P < 0.01). ASC, caspase-1, IL-1β and IL-18 were all expressed in the inflammatory periapical tissues. The positive cell counts of IL-1β and IL-18 were significantly correlated with that of NALP3, and r = 0.718, P < 0.01; r = 0.688, P < 0.01, respectively. CONCLUSIONS NALP3 inflammasome is expressed in the inflammatory periapical tissues. This cytokine-signalling pathway may therefore be crucial in the regulatory control of inflammatory responses in periapical tissues and the development of periapical lesions.
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Affiliation(s)
- S Liu
- Department of Conservative Dentistry and Endodontics, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
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Yamaguchi H, Ozeki N, Kawai R, Tanaka T, Hiyama T, Nakata K, Mogi M, Nakamura H. RETRACTED: Proinflammatory Cytokines Induce Stromelysin-1–mediated Cell Proliferation in Dental Pulp Fibroblast-like Cells. J Endod 2014; 40:89-94. [DOI: 10.1016/j.joen.2013.09.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 09/19/2013] [Accepted: 09/19/2013] [Indexed: 01/26/2023]
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Hiyama T, Ozeki N, Mogi M, Yamaguchi H, Kawai R, Nakata K, Kondo A, Nakamura H. Matrix metalloproteinase-3 in odontoblastic cells derived from ips cells: unique proliferation response as odontoblastic cells derived from ES cells. PLoS One 2013; 8:e83563. [PMID: 24358294 PMCID: PMC3865184 DOI: 10.1371/journal.pone.0083563] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/13/2013] [Indexed: 12/20/2022] Open
Abstract
We previously reported that matrix metalloproteinase (MMP)-3 accelerates wound healing following dental pulp injury. In addition, we reported that a proinflammatory cytokine mixture (tumor necrosis factor-α, interleukin (IL)-1β and interferon-γ) induced MMP-3 activity in odontoblast-like cells derived from mouse embryonic stem (ES) cells, suggesting that MMP-3 plays a potential unique physiological role in wound healing and regeneration of dental pulp in odontoblast-like cells. In this study, we tested the hypothesis that upregulation of MMP-3 activity by IL-1β promotes proliferation and apoptosis of purified odontoblast-like cells derived from induced pluripotent stem (iPS) and ES cells. Each odontoblast-like cell was isolated and incubated with different concentrations of IL-1β. MMP-3 mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. MMP-3 activity was measured using immunoprecipitation and a fluorescence substrate. Cell proliferation and apoptosis were determined using ELISA for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells. Treatment with IL-1β increased MMP-3 mRNA and protein levels, and MMP-3 activity in odontoblast-like cells. Cell proliferation was found to markedly increase with no changes in apoptosis. Endogenous tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 were constitutively expressed during all experiments. The exocytosis inhibitor, Exo1, potently suppressed the appearance of MMP-3 in the conditioned medium. Treatment with siRNA against MMP-3 suppressed an IL-1β-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation, but unexpectedly increased apoptosis in these cells (P<0.05). Exogenous MMP-3 was found to induce cell proliferation in odontoblast-like cells derived from iPS cells and ES cells. This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P<0.05). Taken together, IL-1β induced MMP-3-regulated cell proliferation and suppressed apoptosis in odontoblast-like cells derived from iPS and ES cells.
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Affiliation(s)
- Taiki Hiyama
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Nobuaki Ozeki
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
- * E-mail:
| | - Makio Mogi
- Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Hideyuki Yamaguchi
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Rie Kawai
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Kazuhiko Nakata
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Ayami Kondo
- Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya, Aichi, Japan
| | - Hiroshi Nakamura
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi, Japan
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Wang Y, Zhai S, Wang H, Jia Q, Jiang W, Zhang X, Zhang A, Liu J, Ni L. Absent in melanoma 2 (AIM2) in rat dental pulp mediates the inflammatory response during pulpitis. J Endod 2013; 39:1390-4. [PMID: 24139260 DOI: 10.1016/j.joen.2013.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 07/05/2013] [Accepted: 07/21/2013] [Indexed: 10/26/2022]
Abstract
INTRODUCTION In recent years, the inflammasome has been determined to play an important role in inflammatory diseases. However, the role of the inflammasome in pulpitis remains unclear. Absent in melanoma 2 (AIM2) is a type of inflammasome that recognizes cytosolic double stranded DNA and forms a caspase-1-activating inflammasome with apoptosis-associated speck-like protein containing a caspase activating recruiting domain. In this study, we determined whether AIM2 was expressed in pulp cells and defined the role of AIM2 in the initiation of inflammation within the dental pulp. METHODS In the in vivo study, the right maxillary molars from male adult Sprague-Dawley rats (250-350 g) were exposed to the pulp. In the in vitro study, the pulp cells isolated from the mandibular incisors of the Sprague-Dawley rats (2 weeks) were conventionally cultured. Immunofluorescence staining was used to determine the expression and distribution of AIM2 in the rat dental pulp tissues and cells in the presence or absence of inflammatory stimulation. Western blotting and real-time polymerase chain reaction were performed to determine whether there was a correlation between AIM2 expression levels and inflammation both in vivo and in vitro. RESULTS In healthy dental pulp tissues and cells, AIM2 was only detected in the odontoblast layer. Stimulation significantly increased AIM2 expression in both the dental pulp tissues and cultured cells. The mRNA and protein levels of AIM2 were significantly up-regulated in response to inflammatory stimulation in a dose-dependent manner. Moreover, we also found that AIM2 expression correlated with interleukin-1 levels. These results reveal a direct relationship between the AIM2 inflammasome and pulpitis. CONCLUSIONS Our study demonstrates that AIM2 is expressed in dental pulp tissues and mediates the inflammatory response during pulpitis. Therapeutic interventions aimed at reducing AIM2 expression may be beneficial in the treatment of pulpitis.
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Affiliation(s)
- Yafei Wang
- Department of Operative Dentistry and Endodontics, School of Stomatology, Fourth Military Medical University, Shaanxi, China
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Cooper PR, Smith AJ. Molecular mediators of pulp inflammation and regeneration. ACTA ACUST UNITED AC 2013. [DOI: 10.1111/etp.12036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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