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Saramet V, Stan MS, Ripszky Totan A, Țâncu AMC, Voicu-Balasea B, Enasescu DS, Rus-Hrincu F, Imre M. Analysis of Gingival Fibroblasts Behaviour in the Presence of 3D-Printed versus Milled Methacrylate-Based Dental Resins-Do We Have a Winner? J Funct Biomater 2024; 15:147. [PMID: 38921521 PMCID: PMC11204847 DOI: 10.3390/jfb15060147] [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: 04/22/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/27/2024] Open
Abstract
Computer-aided design and computer-aided manufacturing (CAD/CAM) techniques are based on either subtractive (milling prefabricated blocks) or additive (3D printing) methods, and both are used for obtaining dentistry materials. Our in vitro study aimed to investigate the behavior of human gingival fibroblasts exposed to methacrylate (MA)-based CAD/CAM milled samples in comparison with that of MA-based 3D-printed samples to better elucidate the mechanisms of cell adaptability and survival. The proliferation of human gingival fibroblasts was measured after 2 and 24 h of incubation in the presence of these samples using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the membrane integrity was assessed through the lactate dehydrogenase release. The level of reactive oxygen species, expression of autophagy-related protein LC3B-I, and detection of GSH and caspase 3/7 were evaluated by fluorescence staining. The MMP-2 levels were measured using a Milliplex MAP kit. The incubation with MA-based 3D-printed samples significantly reduced the viability, by 16% and 28% from control after 2 and 24 h, respectively. There was a 25% and 55% decrease in the GSH level from control after 24 h of incubation with the CAD/CAM milled and 3D-printed samples, respectively. In addition, higher levels of LC3B-I and MMP-2 were obtained after 24 h of incubation with the MA-based 3D samples compared to the CAD/CAM milled ones. Therefore, our results outline that the MA-CAD/CAM milled samples displayed good biocompatibility during 24-h exposure, while MA-3D resins are proper for short-term utilization (less than 24 h).
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Affiliation(s)
- Veaceslav Saramet
- Department of Complete Denture, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (V.S.); (M.I.)
| | - Miruna S. Stan
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independentei, 050095 Bucharest, Romania
| | - Alexandra Ripszky Totan
- Department of Biochemistry, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (A.R.T.); (D.S.E.); (F.R.-H.)
- The Interdisciplinary Center for Dental Research and Development, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 17–23 Plevnei Street, 020021 Bucharest, Romania;
| | - Ana Maria Cristina Țâncu
- Department of Complete Denture, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (V.S.); (M.I.)
| | - Bianca Voicu-Balasea
- The Interdisciplinary Center for Dental Research and Development, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 17–23 Plevnei Street, 020021 Bucharest, Romania;
| | - Dan Sebastian Enasescu
- Department of Biochemistry, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (A.R.T.); (D.S.E.); (F.R.-H.)
| | - Florentina Rus-Hrincu
- Department of Biochemistry, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (A.R.T.); (D.S.E.); (F.R.-H.)
| | - Marina Imre
- Department of Complete Denture, Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (V.S.); (M.I.)
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Yang Y, Wang L, Huang Z, Ge L, Shi J. N-acetylcysteine as a novel methacrylate-based resin cement component: effect on cell apoptosis and genotoxicity in human gingival fibroblasts. BMC Oral Health 2024; 24:222. [PMID: 38347533 PMCID: PMC10863190 DOI: 10.1186/s12903-024-03988-2] [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: 05/02/2023] [Accepted: 02/05/2024] [Indexed: 02/15/2024] Open
Abstract
BACKGROUND N-acetylcysteine (NAC) reduces the cytotoxicity and genotoxicity induced by monomers leached from dental composite resins. Herein, we investigated the effects of methacrylate-based resin cement used in dental implant restoration on apoptosis and genotoxicity, as well as the antiapoptotic and antigenotoxic capabilities of its component, NAC. METHODS The antioxidant NAC (0.1 or 1 wt.%) was experimentally incorporated into the methacrylate-based dental resin cement Premier®. The Premier® + NAC (0.1 or 1 wt.%) mixture was subsequently immersed into Dulbecco's modified Eagle's medium for 72 h, and used to treat human gingival fibroblasts (HGFs). The viability of HGFs was determined using the XTT assay. The formation of deoxyribonucleic acid (DNA) double-strand breaks (DNA-DSBs) was determined using a γ-H2AX assay. Reactive oxygen species (ROS), apoptosis, necrosis, and cell cycles were detected and analyzed using flow cytometry. RESULTS The eluate of Premier® significantly inhibited HGF proliferation in vitro by promoting a G1-phase cell cycle arrest, resulting in cell apoptosis. Significant ROS production and DNA-DSB induction were also found in HGFs exposed to the eluate. Incorporating NAC (1 wt.%) into Premier® was found to reduce cell cytotoxicity, the percentage of G1-phase cells, cell apoptosis, ROS production, and DNA-DSB induction. CONCLUSION Incorporating NAC (1 wt.%) into methacrylate-based resin cement Premier® decreases the cell cytotoxicity, ROS production, and DNA-DSBs associated with resin use, and further offers protective effects against the early stages of cell apoptosis and G1-phase cell cycle arrest in HGFs. Overall, our in vitro results indicate that the addition of NAC into methacrylate-based resin cements may have clinically beneficial effects on the cytotoxicity and genotoxicity of these materials.
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Affiliation(s)
- Yang Yang
- Department of Oral Implantology, School and Hospital of Stomatology, Guangdong Engineering Research Center of Oral Restoration and Reconstruction & Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Guangzhou Medical University, Guangzhou, China
| | - Liping Wang
- Department of Oral Implantology, School and Hospital of Stomatology, Guangdong Engineering Research Center of Oral Restoration and Reconstruction & Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Guangzhou Medical University, Guangzhou, China
| | - Zelun Huang
- School and Hospital of Stomatology, Guangdong Engineering Research Center of Oral Restoration and Reconstruction & Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Guangzhou Medical University, Guangzhou, China
| | - Lingu Ge
- School and Hospital of Stomatology, Guangdong Engineering Research Center of Oral Restoration and Reconstruction & Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Guangzhou Medical University, Guangzhou, China
- Suzhou Stomatological Hospital, Suzhan Lu 1366, Suzhou, 215000, China
| | - Jianwei Shi
- Department of Orthodontics, School and Hospital of Stomatology, Guangdong Engineering Research Center of Oral Restoration and Reconstruction & Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Guangzhou Medical University, Guangzhou, China.
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Johnson W, Bergfeld WF, Belsito DV, Cohen DE, Klaassen CD, Liebler DC, Marks JG, Peterson LA, Shank RC, Slaga TJ, Snyder PW, Fiume M, Heldreth B. Methacrylate Ester Monomers. Int J Toxicol 2023; 42:61S-73S. [PMID: 37794531 DOI: 10.1177/10915818231204572] [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] [Indexed: 10/06/2023]
Abstract
The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2005, along with updated information regarding product types and concentrations of use, and confirmed that these 22 methacrylate ester monomers are safe as used in nail enhancement products in the practices of use and concentration as described in this report, when skin contact is avoided.
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Affiliation(s)
- Wilbur Johnson
- Cosmetic Ingredient Review Former Senior Scientific Analyst/Writer
| | | | | | | | | | | | - James G Marks
- Expert Panel for Cosmetic Ingredient Safety Former Member
| | | | - Ronald C Shank
- Expert Panel for Cosmetic Ingredient Safety Former Member
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Sharma S, Khan Q, Schreurs OJF, Sapkota D, Samuelsen JT. Investigation of biological effects of HEMA in 3D-organotypic co-culture models of normal and malignant oral keratinocytes. Biomater Investig Dent 2023; 10:2234400. [PMID: 37456807 PMCID: PMC10348043 DOI: 10.1080/26415275.2023.2234400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023] Open
Abstract
Several in vitro studies utilizing 2-dimensional (2D) cell culture systems have linked 2-hydroxyethyl methacrylate (HEMA) with cytotoxic effects in oral mucosa and dental pulp cells. Although such studies are invaluable in dissecting the cellular and molecular effects of HEMA, there is a growing interest in the utilization of appropriate 3-dimensional (3D) models that mimic the structure of oral mucosa. Using a previously characterized 3D-organotypic co-culture model, this study aimed to investigate the cellular and molecular effects of HEMA on a 3D-co-culture model consisting of primary normal oral keratinocyte (NOK) grown directly on top of collagen I gel containing primary oral fibroblasts (NOF). The second aim was to examine the suitability of a 3D-co-culture system consisting of oral squamous cell carcinoma (OSCC) cells as a model system to investigate the biological effects of HEMA. We demonstrated that HEMA treatment led to reduced viability of NOK, NOF and OSCC-cell lines in 2D-culture. The keratinocytes in 3D-co-cultures of NOK and OSCC-cells reacted similarly with respect to cell proliferation and activation of autophagy flux, to HEMA treatment. Nevertheless, NOK was found to be more susceptible to apoptosis following HEMA treatment than OSCC in 3D-co-cultures. These results indicate that 3D-organotypic co-cultures of NOK might represent an appropriate model system for the investigation of the biological effects of HEMA and other dental biomaterials. Given the challenges in obtaining primary cultures of NOK and issues associated with their rapid differentiation in culture, the possible use of OSCC cells as an alternative to NOK for 3D models represents an area for future research.
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Affiliation(s)
- Sunita Sharma
- Nordic Institute of Dental Materials, Oslo, Norway
- Christiania Dental Clinic, Malo Dental, Oslo, Norway
| | - Qalbi Khan
- Department of Oral Biology, University of Oslo, Oslo, Blindern, Norway
| | | | - Dipak Sapkota
- Department of Oral Biology, University of Oslo, Oslo, Blindern, Norway
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Samuelsen JT, Dahl JE. Biological aspects of modern dental composites. Biomater Investig Dent 2023; 10:2223223. [PMID: 37347059 PMCID: PMC10281392 DOI: 10.1080/26415275.2023.2223223] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 06/05/2023] [Indexed: 06/23/2023] Open
Abstract
Biological evaluation of resin-based dental composites has traditionally been based on in vitro endpoint tests with different methods to determine loss of cell viability and cell morphology changes after exposure to the material or monomer constituents. The data reveals a potential for biological effects, but clinical relevance of such data is limited. Positive allergy tests and allergic clinical reactions to dental monomers are observed in dental personnel and patients. The aim of this review is to address newer research on molecular events caused by exposure to resin-based composites to have a better understanding of the potential for clinical adverse effects. A more accurate understanding of the biological aspects of dental composite materials has been found after studying parameters like glutathione depletion, oxidative stress, genotoxicity, and immunomodulatory key effects in various cell culture models. Using omics-based approaches allow for a broader and non-specified search of changes caused by methacrylate exposure. Defense mechanisms and adaption are observed in cells exposed to monomer concentrations relevant to clinical exposure. The above-mentioned methods are the foundations for modified testing strategies. The clinical relevance of most available in vitro endpoint tests is of limited relevance for the patient. Research focusing on molecular mechanisms has given new insight into methacrylate toxicity in exposed cells. Using this knowledge from mechanistic studies to develop standardized in vitro biocompatibility tests will likely improve their clinical relevance.
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Affiliation(s)
| | - Jon E. Dahl
- NIOM - Nordic institute of dental materials, Oslo, Norway
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6
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Cytotoxicity and Apoptotic Mechanism of 2-Hydroxyethyl Methacrylate via Genotoxicity and the Mitochondrial-Dependent Intrinsic Caspase Pathway and Intracellular Reactive Oxygen Species Accumulation in Macrophages. Polymers (Basel) 2022; 14:polym14163378. [PMID: 36015636 PMCID: PMC9412604 DOI: 10.3390/polym14163378] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/23/2022] Open
Abstract
Macrophages are mainly active cells of the immune system and play a role in the defense of pathogens. However, the overactivation of macrophages by fatal pathogens can result in toxic responses. 2-hydroxyethyl methacrylate (HEMA), which is a hydrophilic monomer, is used in dental adhesive reagents and composite resins as well as biocompatible hydrogels. The mechanisms underlying the genotoxicity engendered by HEMA-induced apoptosis that leads to cytotoxicity remain unclear. Accordingly, this study was conducted to clarify such mechanisms. The results showed that HEMA induced cell toxicity in RAW264.7 macrophages depending on the concentration. A higher HEMA concentration was associated with a higher level of apoptosis and genotoxicity. Moreover, HEMA induced a concentration-dependent increase in mitochondrial dysfunction and the intrinsic caspase pathway, including the activation of caspase-3 and caspase-9. HEMA was also found to upregulate intracellular reactive oxygen species generation and to decrease the activity of antioxidant enzymes, including superoxide dismutase and catalase. Taken together, the mitochondrial-dependent intrinsic caspase pathway and intracellular reactive oxygen species accumulation were found to mediate HEMA-induced genotoxicity and apoptosis, leading to cytotoxicity in RAW264.7 macrophages.
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A novel visible light-curing chitosan-based hydrogel membrane for Guided Tissue Regeneration. Colloids Surf B Biointerfaces 2022; 218:112760. [DOI: 10.1016/j.colsurfb.2022.112760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/02/2022] [Accepted: 08/04/2022] [Indexed: 11/21/2022]
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Kim S, Kim M, Sung JS. Exposure of Toluene Diisocyanate Induces DUSP6 and p53 through Activation of TRPA1 Receptor. Int J Mol Sci 2022; 23:ijms23010517. [PMID: 35008945 PMCID: PMC8745568 DOI: 10.3390/ijms23010517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 01/27/2023] Open
Abstract
Toluene diisocyanate (TDI), a major intermediate agent used in the manufacturing industry, causes respiratory symptoms when exposed to the human body. In this study, we aimed to determine the molecular mechanism of TDI toxicity. To investigate the impact of TDI exposure on global gene expression, we performed transcriptomic analysis of human bronchial epithelial cells (BEAS-2B) after TDI treatment. Differentially expressed genes (DEGs) were sorted and used for clustering and network analysis. Among DEGs, dual-specificity phosphatase 6 (DUSP6) was one of the genes significantly changed by TDI exposure. To verify the expression level of DUSP6 and its effect on lung cells, the mRNA and protein levels of DUSP6 were analyzed. Our results showed that DUSP6 was dose-dependently upregulated by TDI treatment. Thereby, the phosphorylation of ERK1/2, one of the direct inhibitory targets of DUSP6, was decreased. TDI exposure also increased the mRNA level of p53 along with its protein and activity which trans-activates DUSP6. Since TRPA1 is known as a signal integrator activated by TDI, we analyzed the relevance of TRPA1 receptor in DUSP6 regulation. Our data revealed that up-regulation of DUSP6 mediated by TDI was blocked by a specific antagonist against TRPA1. TDI exposure attenuated the apoptotic response, which suggests that it promotes the survival of cancerous cells. In conclusion, our results suggest that TDI induces DUSP6 and p53, but attenuates ERK1/2 activity through TRPA1 receptor activation, leading to cytotoxicity.
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Affiliation(s)
| | - Min Kim
- Correspondence: (M.K.); (J.-S.S.); Tel.: +82-31-961-5132 (J.-S.S.); Fax: +82-31-961-5108 (J.-S.S.)
| | - Jung-Suk Sung
- Correspondence: (M.K.); (J.-S.S.); Tel.: +82-31-961-5132 (J.-S.S.); Fax: +82-31-961-5108 (J.-S.S.)
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Kumaravel TS, Sathya TN, Balaje R, Pradeepa P, Yogaraj D, Murali MR, Navaneethakrishnan KR, Murugan S, Jha AN. Genotoxicity evaluation of medical devices: A regulatory perspective. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2022; 789:108407. [PMID: 35690410 DOI: 10.1016/j.mrrev.2021.108407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 11/22/2021] [Accepted: 11/29/2021] [Indexed: 06/15/2023]
Abstract
This review critically evaluates our current regulatory understanding of genotoxicity testing and risk assessment of medical devices. Genotoxicity risk assessment of these devices begins with the evaluation of materials of construction, manufacturing additives and all residual materials for potential to induce DNA damage. This is followed by extractable and/or leachable (E&L) studies to understand the worst case and/or clinical exposures, coupled with risk assessment of extractables or leachables. The TTC (Threshold of Toxicological Concern) approach is used to define acceptable levels of genotoxic chemicals, when identified. Where appropriate, in silico predictions may be used to evaluate the genotoxic potentials of identifiable chemicals with limited toxicological data and above the levels defined by TTC. Devices that could not be supported by E&L studies are evaluated by in vitro genotoxicity studies conducted in accordance with ISO10993-3 and 33. Certain endpoints such as 'site of contact genotoxicity' that are specific for certain classes of medical devices are currently not addressed in the current standards. The review also illustrates the potential uses of recent advances to achieve the goal of robust genotoxicity assessment of medical devices which are being increasingly used for health benefits. The review also highlights the gaps for genotoxicity risk assessment of medical devices and suggests possible approaches to address them taking into consideration the recent advances in genotoxicity testing including their potential uses in biocompatibility assessment.
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Affiliation(s)
- Tirukalikundram S Kumaravel
- GLR Laboratories (Europe) Pvt. Ltd., Sharnbrook, MK44 1LZ, United Kingdom; GLR Laboratories Pvt Ltd, Chennai, 600068, India.
| | | | | | | | | | | | | | - Sivasubramanian Murugan
- GLR Laboratories (Europe) Pvt. Ltd., Sharnbrook, MK44 1LZ, United Kingdom; GLR Laboratories Pvt Ltd, Chennai, 600068, India
| | - Awadhesh N Jha
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, PL4 8AA, United Kingdom
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Hmar EBL, Paul S, Boruah N, Sarkar P, Borah S, Sharma HK. Apprehending Ulcerative Colitis Management With Springing Up Therapeutic Approaches: Can Nanotechnology Play a Nascent Role? CURRENT PATHOBIOLOGY REPORTS 2021. [DOI: 10.1007/s40139-020-00218-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Zieniewska I, Maciejczyk M, Zalewska A. The Effect of Selected Dental Materials Used in Conservative Dentistry, Endodontics, Surgery, and Orthodontics as Well as during the Periodontal Treatment on the Redox Balance in the Oral Cavity. Int J Mol Sci 2020; 21:ijms21249684. [PMID: 33353105 PMCID: PMC7767252 DOI: 10.3390/ijms21249684] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 12/10/2020] [Accepted: 12/16/2020] [Indexed: 12/31/2022] Open
Abstract
Oxidative stress (OS) is a redox homeostasis disorder that results in oxidation of cell components and thus disturbs cell metabolism. OS is induced by numerous internal as well as external factors. According to recent studies, dental treatment may also be one of them. The aim of our work was to assess the effect of dental treatment on the redox balance of the oral cavity. We reviewed literature available in PubMed, Medline, and Scopus databases, including the results from 2010 to 2020. Publications were searched according to the keywords: oxidative stress and dental monomers; oxidative stress and amalgam; oxidative stress and periodontitis, oxidative stress and braces, oxidative stress and titanium; oxidative stress and dental implants, oxidative stress and endodontics treatment, oxidative stress and dental treatment; and oxidative stress and dental composite. It was found that dental treatment with the use of composites, amalgams, glass-ionomers, materials for root canal filling/rinsing, orthodontic braces (made of various metal alloys), titanium implants, or whitening agents can disturb oral redox homeostasis by affecting the antioxidant barrier and increasing oxidative damage to salivary proteins, lipids, and DNA. Abnormal saliva secretion/composition was also observed in dental patients in the course of OS. It is suggested that the addition of antioxidants to dental materials or antioxidant therapy applied during dental treatment could protect the patient against harmful effects of OS in the oral cavity.
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Affiliation(s)
- Izabela Zieniewska
- Doctoral Studies, Medical University of Bialystok, 24a M. Sklodowskiej-Curie Street, 15-274 Bialystok, Poland
- Correspondence: (I.Z.); (A.Z.)
| | - Mateusz Maciejczyk
- Department of Hygiene, Epidemiology and Ergonomics, Medical University of Bialystok, 15-022 Bialystok, Poland;
| | - Anna Zalewska
- Experimental Dentistry Laboratory, Medical University of Bialystok, 24a M. Sklodowskiej-Curie Street, 15-274 Bialystok, Poland
- Correspondence: (I.Z.); (A.Z.)
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Dental resin monomers induce early and potent oxidative damage on human odontoblast-like cells. Chem Biol Interact 2020; 333:109336. [PMID: 33248029 DOI: 10.1016/j.cbi.2020.109336] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/05/2020] [Accepted: 11/20/2020] [Indexed: 01/10/2023]
Abstract
Resin-based dental materials consist of filler particles and different monomers that are light cured in situ to re-establish dental function and aesthetics. Due to the degree of conversion of adhesive polymers, the monomers triethyleneglycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) are released in relatively high amounts and are susceptible to degradation, acting as bioactive compounds and affecting cell and tissues. This study aimed to assess the effect of HEMA and TEGDMA exposure on metabolic activity, membrane integrity, and cell survival of human odontoblast-like cell (hOLCs). Exposure to resin monomers for 24 h induced major changes in cell membrane integrity, metabolic activity, and survival, which were measured by the calcein method and lactate dehydrogenase release. Increased and early reactive oxygen species (ROS) production was observed leading to degradative oxidation of membrane lipids identified as malondialdehyde production. Severe alteration in mitochondria occurred due to transmembrane mitochondrial potential collapse, possibly inducing activation of apoptotic cell death. hOLCs exposure to resin monomers modified the cell redox potential, with consequences on membrane permeability and integrity, including mitochondrial function. Lipid peroxidation appears to be a key phenomenon for the membrane structures oxidation after HEMA and TEGDMA exposure, leading to cell death and cytotoxicity. hOLCs respond early by differential induction of adaptive mechanisms to maintain cell homeostasis. Modulation of oxidative stress-induced response involves the regulation of genes that encode for antioxidant proteins such as catalase and heme oxygenase-1; regulation that functions as a critical protection mechanism against oxidative cell damage induced by HEMA and TEGDMA. Ascorbic acid as an antioxidant substance mitigates the oxidative damage associated with exposure to monomers.
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13
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Taubmann A, Willershausen I, Walter C, Al-Maawi S, Kaina B, Gölz L. Genotoxic and cytotoxic potential of methacrylate-based orthodontic adhesives. Clin Oral Investig 2020; 25:2569-2581. [PMID: 32970196 PMCID: PMC8060203 DOI: 10.1007/s00784-020-03569-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Accepted: 09/03/2020] [Indexed: 01/01/2023]
Abstract
Objectives The biocompatibility of methacrylate-based adhesives is a topic that is intensively discussed in dentistry. Since only limited evidence concerning the cyto- and genotoxicity of orthodontic adhesives is available, the aim of this study was to measure the genotoxic potential of seven orthodontic methacrylate-based adhesives. Materials and methods The XTT assay was utilized to determine the cytotoxicity of Assure Plus, Assure Bonding Resin, ExciTE F, OptiBond Solo Plus, Scotchbond Universal Adhesive, Transbond MIP, and Transbond XT after an incubation period of 24 h on human gingival fibroblasts. We also performed the γH2AX assay to explore the genotoxic potential of the adhesives within cytotoxic dose ranges after an incubation period of 6 h. Results The XTT assay showed a concentration-dependent reduction in cell viability. The decrease in cellular viability was in the same dose range most significant for Assure Plus, rendering it the adhesive material with the highest cytotoxicity. Employing the γH2AX assay, a concentration-dependent increase in H2AX phosphorylation was detected, indicating induction of DNA damage. Conclusions For most products, a linear correlation between the material concentration and γH2AX foci was observed. The most severe effect on γH2AX focus induction was found for Transbond MIP, which was the only adhesive in the test group containing the co-initiator diphenyliodonium hexafluorophosphate (DPIHP). Clinical relevance The data indicate that orthodontic adhesives, notably Transbond MIP, bear a genotoxic potential. Since the study was performed with in vitro cultivated cells, a direct translation of the findings to in vivo exposure conditions should be considered with great diligence.
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Affiliation(s)
- Andreas Taubmann
- Department of Operative Dentistry, Johannes Gutenberg University Hospital Mainz, Mainz, Germany
| | - Ines Willershausen
- Department of Orthodontics and Orofacial Orthopedics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
| | | | - Sarah Al-Maawi
- Frankfurt Orofacial Regenerative Medicine (FORM) Lab, Department for Oral, Cranio-Maxillofacial and Facial Plastic Surgery, Medical Center of the Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Bernd Kaina
- Institute of Toxicology, University Medical Center Mainz, Mainz, Germany
| | - Lina Gölz
- Department of Orthodontics and Orofacial Orthopedics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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Xu Y, Jacquat RPB, Shen Y, Vigolo D, Morse D, Zhang S, Knowles TPJ. Microfluidic Templating of Spatially Inhomogeneous Protein Microgels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2000432. [PMID: 32529798 DOI: 10.1002/smll.202000432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/20/2020] [Accepted: 05/18/2020] [Indexed: 05/20/2023]
Abstract
3D scaffolds in the form of hydrogels and microgels have allowed for more native cell-culture systems to be developed relative to flat substrates. Native biological tissues are, however, usually spatially inhomogeneous and anisotropic, but regulating the spatial density of hydrogels at the microscale to mimic this inhomogeneity has been challenging to achieve. Moreover, the development of biocompatible synthesis approaches for protein-based microgels remains challenging, and typical gelation conditions include UV light, extreme pH, extreme temperature, or organic solvents, factors which can compromise the viability of cells. This study addresses these challenges by demonstrating an approach to fabricate protein microgels with controllable radial density through microfluidic mixing and physical and enzymatic crosslinking of gelatin precursor molecules. Microgels with a higher density in their cores and microgels with a higher density in their shells are demonstrated. The microgels have robust stability at 37 °C and different dissolution rates through enzymolysis, which can be further used for gradient scaffolds for 3D cell culture, enabling controlled degradability, and the release of biomolecules. The design principles of the microgels could also be exploited to generate other soft materials for applications ranging from novel protein-only micro reactors to soft robots.
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Affiliation(s)
- Yufan Xu
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Raphaël P B Jacquat
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Yi Shen
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Daniele Vigolo
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - David Morse
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Shuyuan Zhang
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
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15
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Chang H, Chen H, Zhang L, Wang Y, Xie X, Zhang Y, Quan F. Effect of oocyte vitrification on DNA damage in metaphase II oocytes and the resulting preimplantation embryos. Mol Reprod Dev 2019; 86:1603-1614. [PMID: 31408251 DOI: 10.1002/mrd.23247] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022]
Abstract
As an assisted reproduction technology, vitrification has been widely used for oocyte and embryo cryopreservation. Many studies have indicated that vitrification affects ultrastructure, gene expression, and epigenetic status. However, it is still controversial whether oocyte vitrification could induce DNA damage in metaphase II (MII) oocytes and the resulting early embryos. This study determined whether mouse oocytes vitrification induce DNA damage in MII oocytes and the resulting preimplantation embryos, and causes for vitrification-induced DNA damage. The effects of oocyte vitrification on reactive oxygen species (ROS) levels, γ-H2AX accumulation, apoptosis, early embryonic development, and the expression of DNA damage-related genes in early embryos derived by in vitro fertilization were examined. The results indicated that vitrification significantly increased the number of γ-H2AX foci in zygotes and two-cell embryos. Trp53bp1 was upregulated in zygotes, two-cell embryos and four-cell embryos in the vitrified group, and Brca1 was increased in two-cell embryos after vitrification. Vitrification also increased the ROS levels in MII oocytes, zygotes, and two-cell embryos and the apoptotic rate in blastocysts. Resveratrol (3,5,4'-trihydroxystilbene) treatment decreased the ROS levels and the accumulation of γ-H2AX foci in zygotes and two-cell embryos and the apoptotic rate in blastocysts after vitrification. Overall, vitrification-induced abnormal ROS generation, γ-H2AX accumulation, an increase in the apoptotic rate and the disruption of early embryonic development. Resveratrol treatment could decrease ROS levels, γ-H2AX accumulation, and the apoptotic rate and improve early embryonic development. Vitrification-associated γ-H2AX accumulation is at least partially due to abnormal ROS generation.
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Affiliation(s)
- Haoya Chang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Huanhuan Chen
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Lei Zhang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yile Wang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaogang Xie
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yong Zhang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Fusheng Quan
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
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16
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Sinjari B, Pizzicannella J, D'Aurora M, Zappacosta R, Gatta V, Fontana A, Trubiani O, Diomede F. Curcumin/Liposome Nanotechnology as Delivery Platform for Anti-inflammatory Activities via NFkB/ERK/pERK Pathway in Human Dental Pulp Treated With 2-HydroxyEthyl MethAcrylate (HEMA). Front Physiol 2019; 10:633. [PMID: 31244665 PMCID: PMC6579913 DOI: 10.3389/fphys.2019.00633] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/06/2019] [Indexed: 01/21/2023] Open
Abstract
Curcumin, primary component of the spice turmeric extracted from the rhizomes of Curcuma longa, represents the major anti-oxidant and anti-inflammatory substance found in turmeric, acting thought various mechanisms not completely understood. Curcumin modulates cytokines, growth factors, transcription factors, inflammatory molecules and cell signaling pathways. During restorative dentistry practice, free resin monomers of 2-hydroxyethyl methacrylate (HEMA) propagate through dentin micro-channel and pulp into the bloodstream affecting cellular integrity. The study highlights the significance of application of curcumin bioactive component into liposomal formulations (CurLIP) to restore the homeostasis of dental pulp stem cells (hDPSCs) in response to 3 and 5 mmol L–1 HEMA treatment. Cell proliferation in combination with changes of the morphological features, proinflammatory cytokines secretion as Interleukin (IL) 6, IL8, Monocyte Chemoattractant Protein-1 (MCP1) and Interferon-gamma (IFNγ) were assayed along with the nuclear factor (NF)-kB, an inducible transcription factor involved in the activation of several cell processes associated to extracellular signal-regulated kinases (ERK) and posphorylated (p-) ERK pathway. Our results showed a decreased cell proliferation, morphological changes and upregulation of IL6, IL8, MCP1 and IFNγ in presence of 3 and 5 mmol L–1 HEMA treatment. CurLIP therapy in hDPSCs provokes an increase in cell proliferation and the block of inflammatory cytokines secretion through the inhibitory regulation of NFkB/ERK and pERK signaling cascade. The natural nanocarrier CurLIP influences numerous biochemical and molecular cascades causing anti-inflammatory properties in response to HEMA treatment in human dental pulp stem cells, representing an innovative endodontic formulation able to improve the quality of dental care with a major human community impact.
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Affiliation(s)
- Bruna Sinjari
- Department of Medical Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti, Italy
| | - Jacopo Pizzicannella
- Department of Medical Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti, Italy.,ASL02 Lanciano-Vasto-Chieti, "Ss. Annunziata" Hospital, Chieti, Italy
| | - Marco D'Aurora
- Department of Psychological, Health and Territorial Sciences, University "G. d'Annunzio", Chieti, Italy
| | | | - Valentina Gatta
- Department of Psychological, Health and Territorial Sciences, University "G. d'Annunzio", Chieti, Italy
| | | | - Oriana Trubiani
- Department of Medical Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti, Italy
| | - Francesca Diomede
- Department of Medical Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti, Italy
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17
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Samuelsen JT, Michelsen VB, Bruun JA, Dahl JE, Jensen E, Örtengren U. The dental monomer HEMA causes proteome changes in human THP-1 monocytes. J Biomed Mater Res A 2019; 107:851-859. [DOI: 10.1002/jbm.a.36601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/16/2018] [Accepted: 12/26/2018] [Indexed: 12/15/2022]
Affiliation(s)
| | | | - Jack-Ansgar Bruun
- Department of Medical Biology, Faculty of Health Sciences; University of Tromsø; Tromsø Norway
| | - Jon E. Dahl
- Nordic Institute of Dental Materials (NIOM); Oslo Norway
| | - Einar Jensen
- Department of Pharmacy, Faculty of Health Sciences; University of Tromsø; Tromsø Norway
| | - Ulf Örtengren
- Department of Clinical Dentistry, Faculty of Health Sciences; University of Tromsø; Tromsø Norway
- Department of Cariology; Institute for Odontology, Sahlgrenska Academy, Göteborg University; Göteborg Sweden
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18
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Juráňová J. Illuminating the cellular and molecular mechanism of the potential toxicity of methacrylate monomers used in biomaterials. Drug Chem Toxicol 2019; 43:266-278. [DOI: 10.1080/01480545.2018.1488860] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jana Juráňová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University, Hněvotínská 3, Olomouc, Czech Republic
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacky University, Hněvotínská 5, Olomouc, Czech Republic
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Nilsen BW, Simon‐Santamaria J, Örtengren U, Jensen E, Bruun J, Michelsen VB, Sørensen KK. Dose- and time-dependent effects of triethylene glycol dimethacrylate on the proteome of human THP-1 monocytes. Eur J Oral Sci 2018; 126:345-358. [PMID: 30051916 PMCID: PMC6585793 DOI: 10.1111/eos.12559] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2018] [Indexed: 12/15/2022]
Abstract
Triethylene glycol dimethacrylate (TEGDMA) is commonly used in polymer resin-based dental materials. This study investigated the molecular mechanisms of TEGDMA toxicity by identifying its time- and dose-dependent effects on the proteome of human THP-1 monocytes. The effects of different concentrations (0.07-5 mM) and exposure times (0-72 h) of TEGDMA on cell viability, proliferation, and morphology were determined using a real-time viability assay, automated cell counting, and electron microscopy, and laid the fundament for choice of exposure scenarios in the proteomic experiments. Solvents were not used, as TEGDMA is soluble in cell culture medium (determined by photon correlation spectroscopy). Cells were metabolically labeled [using the stable isotope labeled amino acids in cell culture (SILAC) strategy], and exposed to 0, 0.3 or 2.5 mM TEGDMA for 6 or 16 h before liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses. Regulated proteins were analyzed in the STRING database. Cells exposed to 0.3 mM TEGDMA showed increased viability and time-dependent upregulation of proteins associated with stress/oxidative stress, autophagy, and cytoprotective functions. Cells exposed to 2.5 mM TEGDMA showed diminished viability and a protein expression profile associated with oxidative stress, DNA damage, mitochondrial dysfunction, and cell cycle inhibition. Altered expression of immune genes was observed in both groups. The study provides novel knowledge about TEGDMA toxicity at the proteomic level. Of note, even low doses of TEGDMA induced a substantial cellular response.
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Affiliation(s)
- Bo W. Nilsen
- Department of Clinical DentistryUiT – The Arctic University of NorwayTromsøNorway
| | | | - Ulf Örtengren
- Department of Clinical DentistryUiT – The Arctic University of NorwayTromsøNorway
- Department of CariologyInstitute of Odontology/Sahlgrenska AcademyGöteborgSweden
| | - Einar Jensen
- Department of PharmacyUiT The Arctic University of NorwayTromsøNorway
| | - Jack‐Ansgar Bruun
- Department of Medical BiologyUiT – The Arctic University of NorwayTromsøNorway
| | | | - Karen K. Sørensen
- Department of Medical BiologyUiT – The Arctic University of NorwayTromsøNorway
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20
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Cell responses to cariogenic microorganisms and dental resin materials—Crosstalk at the dentin-pulp interface? Dent Mater 2017; 33:514-524. [DOI: 10.1016/j.dental.2017.02.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/13/2017] [Accepted: 02/17/2017] [Indexed: 12/22/2022]
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21
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Bolling AK, Solhaug A, Morisbak E, Holme JA, Samuelsen JT. The dental monomer hydroxyethyl methacrylate (HEMA) counteracts lipopolysaccharide-induced IL-1β release-Possible role of glutathione. Toxicol Lett 2017; 270:25-33. [PMID: 28188892 DOI: 10.1016/j.toxlet.2017.02.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 02/03/2017] [Accepted: 02/06/2017] [Indexed: 10/20/2022]
Abstract
Methacrylate monomers, like 2-hydroxyethyl methacrylate (HEMA), are common components of resin based dental materials. Leakage of unpolymerized monomers after placement and curing leads to human exposure. HEMA is known to inhibit lipopolysaccharide (LPS) induced cytokine release. In this study we explore a possible role of the antioxidant glutathione (GSH) in this effect. In the RAW 264.7 murine macrophage cell line, HEMA (<2mM) did not induce cell death, but reduced cellular GSH levels, increased cellular ROS and decreased the IL-1β release from LPS-stimulated cells. Moreover, the IL-1β mRNA levels were reduced after 3-6h exposure, suggesting transcriptional effects of HEMA. The GSH modulators butylsulfoximine (BSO; inhibitor of GSH synthesis) and 2-oxothiazolidine-4-carboxylate (OTC; Cysteine precursor) caused a decrease and increase in the LPS-induced IL-1β release, respectively, suggesting a role for GSH in negative regulation of LPS-induced IL-1β release. However, the magnitude and dynamics of the effects of HEMA and BSO on LPS-induced IL-1β release and GSH depletion differed considerably. Thus, GSH depletion alone could not explain the strong attenuation of LPS-induced IL-1β release caused by HEMA. Formation of HEMA-protein conjugates due to the thiol reactivity of HEMA emerges as a likely candidate for the molecular mechanism accounting for this effect.
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Affiliation(s)
- Anette Kocbach Bolling
- Nordic Institute of Dental Materials, Sognsveien 70A, N-0855 Oslo, Norway; Norwegian Institute of Public Health, Domain of Infection Control and Environmental Health, P.O. Box 4404, N-0403 Oslo, Norway.
| | - Anita Solhaug
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway
| | - Else Morisbak
- Nordic Institute of Dental Materials, Sognsveien 70A, N-0855 Oslo, Norway
| | - Jørn A Holme
- Norwegian Institute of Public Health, Domain of Infection Control and Environmental Health, P.O. Box 4404, N-0403 Oslo, Norway
| | - Jan Tore Samuelsen
- Nordic Institute of Dental Materials, Sognsveien 70A, N-0855 Oslo, Norway
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The lower alkyl methacrylates: Genotoxic profile of non-carcinogenic compounds. Regul Toxicol Pharmacol 2017; 84:77-93. [PMID: 28087335 DOI: 10.1016/j.yrtph.2017.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 01/05/2017] [Accepted: 01/09/2017] [Indexed: 12/22/2022]
Abstract
All of the lower alkyl methacrylates are high production chemicals with potential for human exposure. The genotoxicity of seven mono-functional alkyl esters of methacrylic acid, i.e. methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, n-, i- and t-butyl methacrylate and 2 ethyl hexyl methacrylate, as well as methacrylic acid itself, the acyl component common to all, is reviewed and compared with the lack of carcinogenicity of methyl methacrylate, the representative member of the series so evaluated. Also reviewed are the similarity of structure, chemical and biological reactivity, metabolism and common metabolic products of this group of compounds which allows a category approach for assessing genotoxicity. As a class, the lower alkyl methacrylates are universally negative for gene mutations in prokaryotes but do exhibit high dose clastogenicity in mammalian cells in vitro. There is no convincing evidence that these compounds induce genotoxic effects in vivo in either sub-mammalian or mammalian species. This dichotomy of effects can be explained by the potential genotoxic intermediates generated in vitro. This genotoxic profile of the lower alkyl methacrylates is consistent with the lack of carcinogenicity of methyl methacrylate.
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23
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Chang MC, Tsai YL, Liou EJW, Tang CM, Wang TM, Liu HC, Liao MW, Yeung SY, Chan CP, Jeng JH. Effect of Butyrate on Collagen Expression, Cell Viability, Cell Cycle Progression and Related Proteins Expression of MG-63 Osteoblastic Cells. PLoS One 2016; 11:e0165438. [PMID: 27893752 PMCID: PMC5125573 DOI: 10.1371/journal.pone.0165438] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/11/2016] [Indexed: 01/20/2023] Open
Abstract
Aims Butyric acid is one major metabolic product generated by anaerobic Gram-negative bacteria of periodontal and root canal infection. Butyric acid affects the activity of periodontal cells such as osteoblasts. The purposes of this study were to investigate the effects of butyrate on MG-63 osteoblasts. Methods MG-63 cells were exposed to butyrate and cell viability was estimated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The mRNA and protein expression of type I collagen and cell cycle-related proteins were measured by reverse-transcriptase polymerase chain reaction (RT-PCR), western blotting or immunofluorescent staining. Cellular production of reactive oxygen species (ROS) was analyzed by 2',7'-dichlorofluorescein (DCF) fluorescence flow cytometry. Results Exposure to butyrate suppressed cell proliferation, and induced G2/M (8 and 16 mM) cell cycle arrest of MG-63 cells. Some cell apoptosis was noted. The mRNA expression of cdc2 and cyclin-B1 decreased after exposure to butyrate. The protein expression of type I collagen, cdc2 and cyclin B1 were decreased, whereas the expression of p21, p27 and p57 was stimulated. Under the treatment of butyrate, ROS production in MG-63 cells markedly increased. Conclusions The secretion of butyric acid by periodontal and root canal microorganisms may inhibit bone cell growth and matrix turnover. This is possibly due to induction of cell cycle arrest and ROS generation and inhibition of collagen expression. These results suggest the involvement of butyric acid in the pathogenesis of periodontal and periapical tissue destruction by impairing bone healing responses.
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Affiliation(s)
- Mei-Chi Chang
- Biomedical Science Team, Chang Gung University of Science and Technology, Kwei-Shan, Taoyuan City, Taiwan
- Department of Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan
| | - Yi-Ling Tsai
- Graduate Institute of Clinical Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
| | | | - Chia-Mei Tang
- Graduate Institute of Clinical Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
| | - Tong-Mei Wang
- Graduate Institute of Clinical Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
| | | | - Ming-Wei Liao
- Graduate Institute of Clinical Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
| | - Sin-Yuet Yeung
- Department of Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan
| | - Chiu-Po Chan
- Department of Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan
- * E-mail: (CPC); (JHJ)
| | - Jiiang-Huei Jeng
- Graduate Institute of Clinical Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan
- * E-mail: (CPC); (JHJ)
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24
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Morisbak E, Ansteinsson V, Samuelsen JT. Cell toxicity of 2-hydroxyethyl methacrylate (HEMA): the role of oxidative stress. Eur J Oral Sci 2015; 123:282-7. [DOI: 10.1111/eos.12189] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2015] [Indexed: 12/28/2022]
Affiliation(s)
| | - Vibeke Ansteinsson
- Nordic Institute of Dental Materials; Oslo Norway
- Department of Clinical Dentistry; Faculty of Medicine and Dentistry; University of Bergen; Bergen Norway
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25
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Yang Q, Shi L, Huang K, Xu W. Protective effect of N-acetylcysteine against DNA damage and S-phase arrest induced by ochratoxin A in human embryonic kidney cells (HEK-293). Food Chem Toxicol 2014; 70:40-7. [DOI: 10.1016/j.fct.2014.04.039] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 03/30/2014] [Accepted: 04/25/2014] [Indexed: 12/29/2022]
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Zingler S, Matthei B, Diercke K, Frese C, Ludwig B, Kohl A, Lux CJ, Erber R. Biological evaluation of enamel sealants in an organotypic model of the human gingiva. Dent Mater 2014; 30:1039-51. [PMID: 24993810 DOI: 10.1016/j.dental.2014.06.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 04/03/2014] [Accepted: 06/05/2014] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Various sealant materials have been suggested to decrease decalcification during orthodontic treatment. However, only a few in vitro studies on the cytotoxicity of resinous pit and fissure sealants have been published, and to the best of our knowledge no similar studies are available for the enamel sealants used in orthodontics. Therefore, we aimed to characterize the possible adverse effects of enamel sealants, especially on the gingival epithelium. METHODS Organotypic cultures of the human gingival mucosa were used to assess the possible impact of six enamel sealants. Differentiation and apoptosis were determined by immunofluorescent staining. The pro-inflammatory cytokines IL-1β and IL-6 were quantified by ELISA. Cytotoxicity was measured using MTS assays in monolayer cultures of human gingival fibroblasts. Leaching of monomers from enamel sealants was quantified using HPLC. RESULTS The differentiation of the organotypic gingival mucosa remained unaffected. All under-cured and several standard-cured sealants (Light Bond™ Sealant, Light Bond™ Filled Sealant, and L.E.D. Pro Seal®) significantly induced apoptosis in the organotypic model. Light Bond™ Sealant, Light Bond™ Filled Sealant, and L.E.D. Pro Seal® caused a significant induction of pro-inflammatory cytokines. Reducing curing time had an influence on cytotoxicity in monolayer cultures of primary human oral cells. All resin-based sealants leached monomers. SIGNIFICANCE Enamel sealants might exert adverse effects on the gingival epithelium. Due to the vicinity of the enamel sealant to the gingival epithelium, and the large surface area of applied sealants, these materials should be carefully applied and sufficiently cured.
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Affiliation(s)
- Sebastian Zingler
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Byron Matthei
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Katja Diercke
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Cornelia Frese
- Department of Conservative Dentistry, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Björn Ludwig
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany; Private Practice, Traben-Trarbach, Germany
| | - Annette Kohl
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Christopher J Lux
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - Ralf Erber
- Department of Orthodontics and Dentofacial Orthopedics, Dental School, University of Heidelberg, Heidelberg, Germany.
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2-Hydroxyethyl methacrylate-induced apoptosis through the ATM- and p53-dependent intrinsic mitochondrial pathway. Biomaterials 2014; 35:2890-904. [DOI: 10.1016/j.biomaterials.2013.12.044] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 12/18/2013] [Indexed: 12/31/2022]
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28
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Gallorini M, Cataldi A, di Giacomo V. HEMA-induced cytotoxicity: oxidative stress, genotoxicity and apoptosis. Int Endod J 2014; 47:813-8. [DOI: 10.1111/iej.12232] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/16/2013] [Indexed: 01/14/2023]
Affiliation(s)
- M. Gallorini
- Department of Pharmacy; University “G. d'Annunzio”; Chieti Italy
| | - A. Cataldi
- Department of Pharmacy; University “G. d'Annunzio”; Chieti Italy
| | - V. di Giacomo
- Department of Pharmacy; University “G. d'Annunzio”; Chieti Italy
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29
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Koulaouzidou EA, Touplikioti P, Ziouti F, Papazisis KT. Effects of a dental adhesive on cell cycle regulatory proteins. Dent Mater J 2013; 32:986-91. [PMID: 24240893 DOI: 10.4012/dmj.2013-090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Dental bonding agents may affect the cell cycle patterns and induce cell cycle arrest by blocking its progression. This study tested the cell cycle effects through cyclin-dependent kinase (cdc2) and Rb phosphorylation. Human lung fibroblasts (MRC5) were used for the experiments. The bonding agent tested was the total-etch XP bond. Extracts of the bonding agent were prepared and serial dilutions were tested. The effects of the bonding agent on cell survival, proliferation and DNA synthesis were tested by the SRB and BrdU assays. Analysis of cell cycle distribution was performed by flow cytometry. XP bond exhibited strong inhibition of DNA synthesis and after 48 h of exposure cells were accumulated in the G2/M phase. Cells exposed to the half maximal cell growth inhibitory concentration (IC50) showed an increase in cdc2 kinase and Rb phosphorylation. The results most likely indicate mutagenic effect of the tested agent.
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30
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Lodienė G, Kopperud HM, Ørstavik D, Bruzell EM. Detection of leachables and cytotoxicity after exposure to methacrylate- and epoxy-based root canal sealers in vitro. Eur J Oral Sci 2013; 121:488-96. [DOI: 10.1111/eos.12065] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2013] [Indexed: 12/19/2022]
Affiliation(s)
| | | | - Dag Ørstavik
- Department of Endodontics; Institute of Clinical Dentistry; Faculty of Dentistry; University of Oslo; Oslo; Norway
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Krifka S, Spagnuolo G, Schmalz G, Schweikl H. A review of adaptive mechanisms in cell responses towards oxidative stress caused by dental resin monomers. Biomaterials 2013; 34:4555-63. [DOI: 10.1016/j.biomaterials.2013.03.019] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 03/09/2013] [Indexed: 12/28/2022]
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Garcia-Canton C, Minet E, Anadon A, Meredith C. Metabolic characterization of cell systems used in in vitro toxicology testing: lung cell system BEAS-2B as a working example. Toxicol In Vitro 2013; 27:1719-27. [PMID: 23669205 DOI: 10.1016/j.tiv.2013.05.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/29/2013] [Accepted: 05/01/2013] [Indexed: 12/13/2022]
Abstract
The bioactivation of pro-toxicants is the biological process through which some chemicals are metabolized into reactive metabolites. Therefore, in vitro toxicological evaluation should ideally be conducted in cell systems retaining adequate metabolic competency and relevant to the route of exposure. The respiratory tract is the primary route of exposure to inhaled pro-toxicants and lung-derived BEAS-2B cell line has been considered as a potentially suitable model for in vitro toxicology testing. However, its metabolic activity has not been characterized. We performed a gene expression analysis for 41 metabolism-related genes and compared the profile with liver- and lung-derived cell lines (HepaRG, HepG2 and A549). To confirm that mRNA expression was associated with the corresponding enzyme activity, we used a series of metabolic substrates of CYPs (CYP1A1/1B1, CYP1A2, CYP2A6/2A13 and CYP2E1) known to bioactivate inhaled pro-toxicants. CYP activities were compared between BEAS-2B, HepaRG, HepG2, and A549 cells and published literature on primary bronchial epithelium cells (HBEC). We found that in contrast to HBEC, BEAS-2B and A549 have limited CYP activity which was in agreement with their CYP gene expression profile. Control cell lines such as HepG2 and HepaRG were metabolically active for the tested CYPs. We recommend that similar strategies can be used to select suitable cell systems in the context of pro-toxicant assessment.
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Affiliation(s)
- Carolina Garcia-Canton
- British American Tobacco, Group Research and Development, Regents Park Road, Southampton, Hampshire SO15 8TL, United Kingdom.
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Ansteinsson V, Kopperud HB, Morisbak E, Samuelsen JT. Cell toxicity of methacrylate monomers-The role of glutathione adduct formation. J Biomed Mater Res A 2013; 101:3504-10. [DOI: 10.1002/jbm.a.34652] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 02/04/2013] [Accepted: 02/11/2013] [Indexed: 01/02/2023]
Affiliation(s)
- V. Ansteinsson
- Department of Clinical Dentistry; University of Bergen; Faculty of Medicine and Dentistry; Bergen Norway
- Nordic Institute of Dental Materials (NIOM); PO Box 3874 Ullevaal stadion N-0805 Oslo Norway
| | - H. B. Kopperud
- Nordic Institute of Dental Materials (NIOM); PO Box 3874 Ullevaal stadion N-0805 Oslo Norway
| | - E. Morisbak
- Nordic Institute of Dental Materials (NIOM); PO Box 3874 Ullevaal stadion N-0805 Oslo Norway
| | - J. T. Samuelsen
- Nordic Institute of Dental Materials (NIOM); PO Box 3874 Ullevaal stadion N-0805 Oslo Norway
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Funakoshi M, Yamaguchi M, Asano M, Fujita S, Kasai K. Effect of Compression Force on Apoptosis in Human Periodontal Ligament Cells. J HARD TISSUE BIOL 2013. [DOI: 10.2485/jhtb.22.41] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Cataldi A, Zara S, Rapino M, Patruno A, di Giacomo V. Human gingival fibroblasts stress response to HEMA: A role for protein kinase C α. J Biomed Mater Res A 2012; 101:378-84. [DOI: 10.1002/jbm.a.34337] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 05/18/2012] [Accepted: 06/26/2012] [Indexed: 11/10/2022]
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Chang MC, Tsai YL, Chen YW, Chan CP, Huang CF, Lan WC, Lin CC, Lan WH, Jeng JH. Butyrate induces reactive oxygen species production and affects cell cycle progression in human gingival fibroblasts. J Periodontal Res 2012; 48:66-73. [PMID: 22834967 DOI: 10.1111/j.1600-0765.2012.01504.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND AND OBJECTIVE Short-chain fatty acids, such as butyric acid and propionic acid, are metabolic by-products generated by periodontal microflora such as Porphyromonas gingivalis, and contribute to the pathogenesis of periodontitis. However, the effects of butyrate on the biological activities of gingival fibroblasts (GFs) are not well elucidated. MATERIAL AND METHODS Human GFs were exposed to various concentrations of butyrate (0.5-16 mm) for 24 h. Viable cells that excluded trypan blue were counted. Cell cycle distribution of GFs was analyzed by propidium iodide-staining flow cytometry. Cellular reactive oxygen species (ROS) production was measured by flow cytometry using 2',7'-dichlorofluorescein (DCF). Total RNA and protein lysates were isolated and subjected to RT-PCR using specific primers or to western blotting using specific antibodies, respectively. RESULTS Butyrate inhibited the growth of GFs, as indicated by a decrease in the number of viable cells. This event was associated with an induction of G0/G1 and G2/M cell cycle arrest by butyrate (4-16 mm) in GFs. However, no marked apoptosis of GFs was noted in this experimental condition. Butyrate (> 2 mm) inhibited the expression of cdc2, cdc25C and cyclinB1 mRNAs and reduced the levels of Cdc2, Cdc25C and cyclinB1 proteins in GFs, as determined using RT-PCR and western blotting, respectively. This toxic effect of butyrate was associated with the production of ROS. CONCLUSION These results suggest that butyrate generated by periodontal pathogens may be involved in the pathogenesis of periodontal diseases via the induction of ROS production and the impairment of cell growth, cell cycle progression and expression of cell cycle-related genes in GFs. These events are important in the initiation and prolongation of inflammatory processes in periodontal diseases.
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Affiliation(s)
- M-C Chang
- Biomedical Science Team, Chang Gung University of Science and Technology, Taoyuan, Taiwan
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Garcia-Canton C, Anadón A, Meredith C. γH2AX as a novel endpoint to detect DNA damage: applications for the assessment of the in vitro genotoxicity of cigarette smoke. Toxicol In Vitro 2012; 26:1075-86. [PMID: 22735693 DOI: 10.1016/j.tiv.2012.06.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 05/17/2012] [Accepted: 06/14/2012] [Indexed: 01/02/2023]
Abstract
Histone H2AX is rapidly phosphorylated to become γH2AX after exposure to DNA-damaging agents that cause double-strand DNA breaks (DSBs). γH2AX can be detected and quantified by numerous methods, giving a direct correlation with the number of DSBs. This relationship has made γH2AX an increasingly utilised endpoint in multiple scientific fields since its discovery in 1998. Applications include its use in pre-clinical drug assessment, as a biomarker of DNA damage and in in vitro mechanistic studies. Here, we review current in vitro regulatory and non-regulatory genotoxicity assays proposing the γH2AX assay as a potential complement to the current test battery. Additionally, we evaluate the use of the γH2AX assay to measure DSBs in vitro in tobacco product testing.
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Affiliation(s)
- Carolina Garcia-Canton
- British American Tobacco, Group Research and Development, Regents Park Road, Southampton, Hampshire SO15 8TL, UK.
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Enniatin B-induced cell death and inflammatory responses in RAW 267.4 murine macrophages. Toxicol Appl Pharmacol 2012; 261:74-87. [PMID: 22483798 DOI: 10.1016/j.taap.2012.03.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Revised: 03/12/2012] [Accepted: 03/19/2012] [Indexed: 12/11/2022]
Abstract
The mycotoxin enniatin B (EnnB) is predominantly produced by species of the Fusarium genera, and often found in grain. The cytotoxic effect of EnnB has been suggested to be related to its ability to form ionophores in cell membranes. The present study examines the effects of EnnB on cell death, differentiation, proliferation and pro-inflammatory responses in the murine monocyte-macrophage cell line RAW 264.7. Exposure to EnnB for 24 h caused an accumulation of cells in the G0/G1-phase with a corresponding decrease in cyclin D1. This cell cycle-arrest was possibly also linked to the reduced cellular ability to capture and internalize receptors as illustrated by the lipid marker ganglioside GM1. EnnB also increased the number of apoptotic, early apoptotic and necrotic cells, as well as cells with elongated spindle-like morphology. The Neutral Red assay indicated that EnnB induced lysosomal damage; supported by transmission electron microscopy (TEM) showing accumulation of lipids inside the lysosomes forming lamellar structures/myelin bodies. Enhanced levels of activated caspase-1 were observed after EnnB exposure and the caspase-1 specific inhibitor ZYVAD-FMK reduced EnnB-induced apoptosis. Moreover, EnnB increased the release of interleukin-1 beta (IL-1β) in cells primed with lipopolysaccharide (LPS), and this response was reduced by both ZYVAD-FMK and the cathepsin B inhibitor CA-074Me. In conclusion, EnnB was found to induce cell cycle arrest, cell death and inflammation. Caspase-1 appeared to be involved in the apoptosis and release of IL-1β and possibly activation of the inflammasome through lysosomal damage and leakage of cathepsin B.
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