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Chackartchi T, Bosshardt DD, Imber JC, Stähli A, Sacks H, Nagy K, Sculean A. Histological evaluation following treatment of recession-type defects with coronally advanced flap and a novel human recombinant amelogenin. Clin Oral Investig 2023; 27:5041-5048. [PMID: 37421492 PMCID: PMC10492744 DOI: 10.1007/s00784-023-05123-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 06/14/2023] [Indexed: 07/10/2023]
Abstract
OBJECTIVES To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects. MATERIALS AND METHODS A total of 17 gingival recession-type defects were surgically created in the maxilla of three minipigs. The defects were randomly treated with a coronally advanced flap (CAF) and either rAmelX (test), or a CAF and placebo (control). At three months following reconstructive surgery, the animals were euthanized, and the healing outcomes histologically evaluated. RESULTS The test group yielded statistically significantly (p = 0.047) greater formation of cementum with inserting collagen fibers compared with the control group (i.e., 4.38 mm ± 0.36 mm vs. 3.48 mm ± 1.13 mm). Bone formation measured 2.15 mm ± 0.8 mm in the test group and 2.24 mm ± 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94). CONCLUSIONS The present data have provided for the first-time evidence for the potential of rAmelX to promote regeneration of periodontal ligament and root cementum in recession-type defects, thus warranting further preclinical and clinical testing. CLINICAL RELEVANCE The present results set the basis for the potential clinical application of rAmelX in reconstructive periodontal surgery.
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Affiliation(s)
- Tali Chackartchi
- Department of Periodontology, Hadassah Medical Center, Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dieter D Bosshardt
- Department of Periodontology, Hadassah Medical Center, Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Robert K. Schenk Laboratory of Oral Histology, Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Jean-Claude Imber
- Department of Periodontology, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010, Bern, Switzerland
| | - Alexandra Stähli
- Department of Periodontology, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010, Bern, Switzerland
| | | | - Katalin Nagy
- Department of Oral Surgery, Faculty of Dentistry, University of Szeged, Szeged, Hungary
| | - Anton Sculean
- Department of Periodontology, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010, Bern, Switzerland.
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Fraser D, Caton J, Benoit DSW. Periodontal Wound Healing and Regeneration: Insights for Engineering New Therapeutic Approaches. FRONTIERS IN DENTAL MEDICINE 2022. [DOI: 10.3389/fdmed.2022.815810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Periodontitis is a widespread inflammatory disease that leads to loss of the tooth supporting periodontal tissues. The few therapies available to regenerate periodontal tissues have high costs and inherent limitations, inspiring the development of new approaches. Studies have shown that periodontal tissues have an inherent capacity for regeneration, driven by multipotent cells residing in the periodontal ligament (PDL). The purpose of this review is to describe the current understanding of the mechanisms driving periodontal wound healing and regeneration that can inform the development of new treatment approaches. The biologic basis underlying established therapies such as guided tissue regeneration (GTR) and growth factor delivery are reviewed, along with examples of biomaterials that have been engineered to improve the effectiveness of these approaches. Emerging therapies such as those targeting Wnt signaling, periodontal cell delivery or recruitment, and tissue engineered scaffolds are described in the context of periodontal wound healing, using key in vivo studies to illustrate the impact these approaches can have on the formation of new cementum, alveolar bone, and PDL. Finally, design principles for engineering new therapies are suggested which build on current knowledge of periodontal wound healing and regeneration.
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Effects of Obesity on Bone Healing in Rats. Int J Mol Sci 2021; 22:ijms222413339. [PMID: 34948136 PMCID: PMC8704371 DOI: 10.3390/ijms222413339] [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: 10/31/2021] [Revised: 12/05/2021] [Accepted: 12/07/2021] [Indexed: 12/12/2022] Open
Abstract
Although the association between periodontitis and obesity is well explored, it is unclear whether obesity is associated with a worse therapeutic outcome after periodontal treatment. The aim of this study was to investigate the effects of obesity on bone healing with and without the application of regeneration-promoting molecules. A standardized bone fenestration-type defect was created over the root of the mandibular first molar in 15 Wistar rats. Ten animals received a high-fat, high-sucrose diet (HFSD), while the remaining five animals were fed a standard diet. During surgery, the fenestration defects from half of the HFSD-fed, i.e., obese animals, were treated with regeneration-promoting molecules (enamel matrix derivative; EMD). After four weeks, bone healing was evaluated by histomorphometry, TRAP staining and immunohistochemistry for RUNX2 and osteopontin. The analyses revealed that the spontaneous healing of the periodontal defects was compromised by obesity. Application of EMD partially compensated for the negative effect of obesity. Nevertheless, EMD-stimulated bone healing in obese animals was not better than the spontaneous healing in the obesity-free control group, indicating that obesity may also inhibit the stimulatory effects of regeneration-promoting molecules. Our results show that obesity can negatively influence bone healing and suggest that bone healing may be compromised in humans.
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Osteoprotective Effect of Enamel Matrix Derivatives on the Regeneration of Mandibular Defects in Experimentally Glucocorticoid-Induced Osteoporosis. Int J Dent 2021; 2021:8659010. [PMID: 34804167 PMCID: PMC8598373 DOI: 10.1155/2021/8659010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/12/2021] [Accepted: 09/29/2021] [Indexed: 11/17/2022] Open
Abstract
Purpose Osteoporosis is a progressive systematic skeletal illness characterized by low bone mineral density and susceptibility to fracture caused by bone resorption. Aim of the Study. This study intended to evaluate the possible role of emdogain in combination with calcitonin on the healing of surgically induced mandibular defects performed on osteoporotic rats. Materials and Methods Forty healthy female white albino rats were included in this study and divided into four groups. In group I (negative control), 10 rats received a vehicle injection after which a unilateral mandibular defect was created in each rat of all groups. Three groups were subjected to induction of osteoporosis by subcutaneous injection of 0.1 mg/kg/day dexamethasone for 60 days. In group II, rats were kept without treatment. In group III, rats were treated with daily intramuscular injection of 2.5 IU/kg of synthetic salmon calcitonin. In group IV, rats were handled as group III, and the created cavity was filled with emdogain. Rats were euthanized at 2nd and 4th week postsurgically. Hematoxylin and eosin, Masson's trichrome, NF-κB (nuclear factor of activated B cells), and immunohistochemical stains were used, followed by statistical analysis. Results Group I showed normal stages of bone defects healing. Group II revealed the formation of granulation tissue with dilated blood vessels, while groups III and IV showed enhanced bone healing and proper collagen fibers. The percentage area of newly formed collagen fibers was significantly higher in group IV at 2nd week (13.96 ± 0.020%) and 4th week (16.95 ± 0.024%) than in group II (8.75 ± 0.015% and 10.29 ± 0.015%, respectively) and group III (12.93 ± 0.015% and 14.61 ± 0.021%, respectively), but was lower than that in group I (15.75 ± 0.015% and 17.49 ± 0.015%, respectively). Conclusion The local application of emdogain combined with systemically injected calcitonin improves bone healing in surgically induced bone defects in osteoporotic rats.
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Amelogenin-Derived Peptides in Bone Regeneration: A Systematic Review. Int J Mol Sci 2021; 22:ijms22179224. [PMID: 34502132 PMCID: PMC8431254 DOI: 10.3390/ijms22179224] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/03/2021] [Accepted: 08/11/2021] [Indexed: 11/17/2022] Open
Abstract
Amelogenins are enamel matrix proteins currently used to treat bone defects in periodontal surgery. Recent studies have highlighted the relevance of amelogenin-derived peptides, named LRAP, TRAP, SP, and C11, in bone tissue engineering. Interestingly, these peptides seem to maintain or even improve the biological activity of the full-length protein, which has received attention in the field of bone regeneration. In this article, the authors combined a systematic and a narrative review. The former is focused on the existing scientific evidence on LRAP, TRAP, SP, and C11's ability to induce the production of mineralized extracellular matrix, while the latter is concentrated on the structure and function of amelogenin and amelogenin-derived peptides. Overall, the collected data suggest that LRAP and SP are able to induce stromal stem cell differentiation towards osteoblastic phenotypes; specifically, SP seems to be more reliable in bone regenerative approaches due to its osteoinduction and the absence of immunogenicity. However, even if some evidence is convincing, the limited number of studies and the scarcity of in vivo studies force us to wait for further investigations before drawing a solid final statement on the real potential of amelogenin-derived peptides in bone tissue engineering.
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Durstberger G, Nguyen PQ, Hohensinner V, Pietschmann P, Rausch-Fan X, Andrukhov O. Effect of Enamel Matrix Derivatives on Osteoclast Formation from PBMC of Periodontitis Patients and Healthy Individuals after Interaction with Activated Endothelial Cells. ACTA ACUST UNITED AC 2021; 57:medicina57030269. [PMID: 33804249 PMCID: PMC7998895 DOI: 10.3390/medicina57030269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/10/2021] [Accepted: 03/12/2021] [Indexed: 02/07/2023]
Abstract
Background and objectives: Enamel matrix derivative (EMD) is produced from developing porcine tooth buds and represents a complex of low-molecular-weight hydrophobic enamel proteins. EMD is widely applied in periodontal regeneration. Osteoclasts are multinuclear cells, which are responsible for bone resorption. The precursors of osteoclasts, hematopoietic cells, undergo in vivo the process of transendothelial migration before differentiation. EMD is known to affect the process of osteoclastogenesis, but its effect on human osteoclasts precursors after the interaction with activated endothelium was never studied. Materials and Methods: Human umbilical vein endothelial cells (HUVECs)s were seeded in transwell inserts with a pore size of 8 µm and pre-activated by TNF-α and IL-1β for 18 h. Peripheral blood mononuclear cells (PBMCs), freshly isolated from 16 periodontitis patients and 16 healthy individuals, were added to pre-activated HUVECs. Adherent, non-adherent and transmigrated cells were collected and differentiated to osteoclasts by the standard protocol in the presence or absence of EMD. The number of osteoclasts was determined by tartrate-resistant acid phosphatase staining. Results: PBMCs isolated from periodontitis patients have formed a significantly higher osteoclast number compared to PBMCs isolated from healthy individuals (p < 0.05). EMD induced concentration-dependent inhibition of osteoclast formation from PBMCs. This was true for the different PBMC fractions isolated from both healthy individuals and periodontitis patients. Conclusions: Our data show that EMD inhibits the formation and activity of osteoclasts differentiated from the progenitor cells after the interaction with activated endothelium. This might be associated with bone resorption inhibition and supporting bone regeneration in the frame of periodontal therapy.
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Affiliation(s)
- Gerlinde Durstberger
- Division of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria; (G.D.); (X.R.-F.)
| | - Phuong Quynh Nguyen
- Competence Center for Periodontal Research, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria;
| | - Verena Hohensinner
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immuology, Medical University of Vienna, 1090 Vienna, Austria; (V.H.); (P.P.)
| | - Peter Pietschmann
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immuology, Medical University of Vienna, 1090 Vienna, Austria; (V.H.); (P.P.)
| | - Xiaohui Rausch-Fan
- Division of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria; (G.D.); (X.R.-F.)
| | - Oleh Andrukhov
- Competence Center for Periodontal Research, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria;
- Correspondence:
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Shaikh MS, Ullah R, Lone MA, Matabdin H, Khan F, Zafar MS. Periodontal regeneration: a bibliometric analysis of the most influential studies. Regen Med 2020; 14:1121-1136. [PMID: 31957597 DOI: 10.2217/rme-2019-0019] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Aim: The aim of the present study is to identify the most influential research articles and their main characteristics in the specialty of periodontal regeneration. Materials & methods: The Web of Science database advance search was performed in the subject category of 'Dentistry, Oral surgery and medicine' from January 2004 to October 2018 to retrieve citations data. Results: The majority of the articles were published in journals dedicated to the specialty of periodontology. Among the top-cited articles most emphasized study types were randomized control trials (n = 25) and reviews (n = 20). Conclusion: The present bibliometric analysis provides comprehensive information regarding the contributions made in the advancement of regenerative periodontal research. The authors from developed countries and affiliated with interdisciplinary/multicenter institutions have predominantly contributed.
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Affiliation(s)
- Muhammad S Shaikh
- Department of Oral Biology, Sindh Institute of Oral Health Sciences, Jinnah Sindh Medical University Karachi, Pakistan
| | - Rizwan Ullah
- Department of Oral Biology, Sindh Institute of Oral Health Sciences, Jinnah Sindh Medical University Karachi, Pakistan
| | - Mohid A Lone
- Department of Oral Pathology, Sindh Institute of Oral Health Sciences, Jinnah Sindh Medical University Karachi, Pakistan
| | - Hesham Matabdin
- Department of Periodontics, Eastman Dental Institute, University College London, London, UK
| | - Fahad Khan
- Faculty of Healthcare & Medical Sciences, Anglia Ruskin University Cambridge, UK
| | - Muhammad S Zafar
- Department of Restorative Dentistry, Taibah University, Madina Munawwarra, Saudi Arabia.,Department of Dental Materials, Islamic International Dental College, Riphah International University, Islamabad, Pakistan
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Kobayashi E, Fujioka‐Kobayashi M, Saulacic N, Schaller B, Sculean A, Miron RJ. Effect of enamel matrix derivative liquid in combination with a natural bone mineral on new bone formation in a rabbit GBR model. Clin Oral Implants Res 2019; 30:542-549. [DOI: 10.1111/clr.13440] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 09/09/2018] [Accepted: 09/22/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Eizaburo Kobayashi
- Department of Cranio‐Maxillofacial Surgery, Inselspital, Bern University Hospital University of Bern Bern Switzerland
- Department of Oral and Maxillofacial Surgery, School of Life, Dentistry at Niigata The Nippon Dental University Niigata Japan
| | - Masako Fujioka‐Kobayashi
- Department of Cranio‐Maxillofacial Surgery, Inselspital, Bern University Hospital University of Bern Bern Switzerland
| | - Nikola Saulacic
- Department of Cranio‐Maxillofacial Surgery, Inselspital, Bern University Hospital University of Bern Bern Switzerland
| | - Benoit Schaller
- Department of Cranio‐Maxillofacial Surgery, Inselspital, Bern University Hospital University of Bern Bern Switzerland
| | - Anton Sculean
- Department of Periodontology University of Bern Bern Switzerland
| | - Richard J. Miron
- Department of Periodontology University of Bern Bern Switzerland
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9
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Split-mouth evaluation of connective tissue graft with or without enamel matrix derivative for the treatment of isolated gingival recession defects in dogs. Clin Oral Investig 2018; 23:3339-3349. [PMID: 30506228 DOI: 10.1007/s00784-018-2750-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 11/21/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVES The potential additive effect of an enamel matrix derivative (EMD) to a subepithelial connective tissue graft (CTG) for recession coverage is still controversially discussed. Therefore, the aim of this study was to histologically evaluate the healing of gingival recessions treated with coronally advanced flap (CAF) and CTG with or without EMD in dogs. MATERIALS AND METHODS Gingival recession defects (5 mm wide and 7 mm deep) were surgically created on the labial side of bilateral maxillary canines in 7 dogs. After 8 weeks of plaque accumulation and subsequent 2 weeks of chemical plaque control, the 14 chronic defects were randomized to receive either CAF with CTG (CAF/CTG) or CAF with CTG and EMD (CAF/CTG/EMD). The animals were sacrificed 10 weeks after reconstructive surgery for histologic evaluation. RESULTS Treatment with CAF/CTG/EMD demonstrated statistically significantly better results in terms of probing pocket depth reduction (P < 0.05) and clinical attachment level gain (P < 0.001). The length of the epithelium was statistically significantly shorter in the CAF/CTG/EMD group than in the CAF/CTG group (1.00 ± 0.75 mm vs. 2.38 ± 1.48 mm, respectively, P < 0.01). Cementum formation was statistically significantly greater in the CAF/CTG/EMD group than following treatment with the CAF/CTG group (3.20 ± 0.89 mm vs. 1.88 ± 1.58 mm, respectively, P < 0.01). The CAF/CTG/EMD group showed statistically significantly greater complete periodontal regeneration (i.e., new cementum, new periodontal ligament, and new bone) than treatment with CAF/CTG (0.54 ± 0.73 mm vs. 0.07 ± 0.27 mm, respectively, P < 0.05). CONCLUSION Within their limits, the present findings indicate that the additional use of EMD in conjunction with CAF + CTG favors periodontal regeneration in gingival recession defects. CLINICAL RELEVANCE The present findings support the use of EMD combined with CTG and CAF for promoting periodontal regeneration in isolated gingival recession defects.
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10
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Song M, Yu B, Kim S, Hayashi M, Smith C, Sohn S, Kim E, Lim J, Stevenson RG, Kim RH. Clinical and Molecular Perspectives of Reparative Dentin Formation: Lessons Learned from Pulp-Capping Materials and the Emerging Roles of Calcium. Dent Clin North Am 2018; 61:93-110. [PMID: 27912821 DOI: 10.1016/j.cden.2016.08.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The long-term use of calcium hydroxide and the recent increase in the use of hydraulic calcium-silicate cements as direct pulp-capping materials provide important clues in terms of how reparative dentin may be induced to form a "biological seal" to protect the underlying pulp tissues. In this review article, we discuss clinical and molecular perspectives of reparative dentin formation based on evidence learned from the use of these pulp-capping materials. We also discuss the emerging role of calcium as an odontoinductive component in these pulp-capping materials.
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Affiliation(s)
- Minju Song
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA; Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Bo Yu
- Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Sol Kim
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA; Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Marc Hayashi
- Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Colby Smith
- Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Suhjin Sohn
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Euiseong Kim
- Microscope Center, Department of Conservative Dentistry, Oral Science Research Center, Yonsei University College of Dentistry, 50 Yonsei-Ro, 03772, Seoul, Korea
| | - James Lim
- Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Richard G Stevenson
- Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA
| | - Reuben H Kim
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA; Section of Restorative Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA.
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11
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Wang HH, Sarmast ND, Shadmehr E, Angelov N, Shabahang S, Torabinejad M. Application of Enamel Matrix Derivative (Emdogain) in Endodontic Therapy: A Comprehensive Literature Review. J Endod 2018; 44:1066-1079. [DOI: 10.1016/j.joen.2018.02.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 01/25/2018] [Accepted: 02/10/2018] [Indexed: 01/28/2023]
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12
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Song B, Zhang H, Zhang S. Toll‑like receptor 2 mediates deposition of collagen I in adipose tissue of high fat diet‑induced obese mice. Mol Med Rep 2018; 17:5958-5963. [PMID: 29436650 DOI: 10.3892/mmr.2018.8590] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 11/23/2017] [Indexed: 11/06/2022] Open
Abstract
Obesity is marked by deposition of collagen I in adipose tissue. Toll like receptor (TLR)2 is involved in lipid metabolism, however the association between TLR2 and collagen I remains unclear. The present study was designed to investigate the effect of TLR2 knockout on collagen I in adipose tissue in obese mice. TLR2 knockout and C57BL/6J mice (aged 4 weeks) were fed normal chow or a high‑fat‑diet for 16 weeks. Compared with adipose tissue from lean controls, that from C57BL/6J mice fed a high‑fat diet had increased levels of collagen I, TIMP1 and TGFβ1 and lower levels of MMP1. However, adipose tissue from TLR2 knockout mice fed a high‑fat diet revealed decreased levels of collagen I, TIMP metallopeptidase inhibitor (TIMP)1, and transforming growth factor (TGF)β1, in addition to increased levels of matrix metallopeptidase (MMP)1. These findings suggest that, in the adipose tissue of obese mice, TLR2 is involved in the metabolism of collagen I and may exhibit a role in the metabolism of MMP1, TIMP1 and TGFβ1.
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Affiliation(s)
- Bing Song
- Endocrinology Department, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
| | - Haoqiang Zhang
- Endocrinology Department, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
| | - Suping Zhang
- Endocrinology Department, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
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13
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Takeuchi N, Shirakata Y, Shinohara Y, Sena K, Noguchi K. Periodontal wound healing following reciprocal autologous root transplantation in class III furcation defects. J Periodontal Implant Sci 2018; 47:352-362. [PMID: 29333321 PMCID: PMC5764761 DOI: 10.5051/jpis.2017.47.6.352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 11/10/2017] [Indexed: 01/09/2023] Open
Abstract
Purpose Furcation involvement in the molars is difficult to treat, and has been recognized as a risk factor for tooth loss. Although periodontal regenerative therapies, including guided tissue regeneration and various types of bone grafts, have been applied to furcation defects, the effects of these treatments are limited, especially in large class III furcation defects. The purpose of this pilot study was to investigate the effect of reciprocal autologous root transplantation on periodontal wound healing and regeneration in class III furcation defects in dogs. Methods Furcation defects (7 mm wide and 6 mm high) were surgically created after root separation of the unilateral third and fourth premolars in 4 dogs. Eight furcation defects were randomized to receive either reciprocal autologous root transplantation (test) or no further treatment (control). In the test group, the mesial and distal roots were transplanted into the distal and mesial extraction sockets, respectively. The animals were sacrificed 10 weeks after surgery for histologic evaluation. Results The healing pattern in the control group was characterized by extensive collapse of the flap and limited periodontal regeneration. New bone formation in the test group (3.56±0.57 mm) was significantly greater than in the control group (0.62±0.21 mm). Dense collagen fibers inserting into the residual cementum on the transplanted root surfaces were observed in the test group. Slight ankylosis was observed in 2 of the 4 specimens in the test group on the mesiodistal sides where the root-planed surfaces faced the existing bone. Root resorption (RR) was detected in both the control and test groups. Conclusions Within the limits of this study, it can be concluded that reciprocal autologous root transplantation was effective for bone regeneration in class III furcation defects in dogs. However, further studies are required to standardize the approach in order to prevent unwanted RR prior to clinical application.
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Affiliation(s)
- Naoshi Takeuchi
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yoshinori Shirakata
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yukiya Shinohara
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Kotaro Sena
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Kazuyuki Noguchi
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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14
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Stähli A, Miron RJ, Bosshardt DD, Sculean A, Gruber R. Collagen Membranes Adsorb the Transforming Growth Factor-β Receptor I Kinase-Dependent Activity of Enamel Matrix Derivative. J Periodontol 2016; 87:583-90. [PMID: 26777762 DOI: 10.1902/jop.2016.150538] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Enamel matrix derivative (EMD) and collagen membranes (CMs) are simultaneously applied in regenerative periodontal surgery. The aim of this study is to evaluate the ability of two CMs and a collagen matrix to adsorb the activity intrinsic to EMD that provokes transforming growth factor (TGF)-β signaling in oral fibroblasts. METHODS Three commercially available collagen products were exposed to EMD or recombinant TGF-β1, followed by vigorous washing. Oral fibroblasts were either seeded directly onto collagen products or were incubated with the respective supernatant. Expression of TGF-β target genes interleukin (IL)-11 and proteoglycan 4 (PRG4) was evaluated by real time polymerase chain reaction. Proteomic analysis was used to study the fraction of EMD proteins binding to collagen. RESULTS EMD or TGF-β1 provoked a significant increase of IL-11 and PRG4 expression of oral fibroblasts when seeded onto collagen products and when incubated with the respective supernatant. Gene expression was blocked by the TGF-β receptor I kinase inhibitor SB431542. Amelogenin bound most abundantly to gelatin-coated culture dishes. However, incubation of palatal fibroblasts with recombinant amelogenin did not alter expression of IL-11 and PRG4. CONCLUSION These in vitro findings suggest that collagen products adsorb a TGF-β receptor I kinase-dependent activity of EMD and make it available for potential target cells.
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Affiliation(s)
- Alexandra Stähli
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Richard J Miron
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.,Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern
| | - Dieter D Bosshardt
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.,Robert K. Schenk Laboratory of Oral Histology, School of Dental Medicine, University of Bern
| | - Anton Sculean
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Reinhard Gruber
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.,Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern.,Department of Oral Biology, Medical University of Vienna, Vienna, Austria
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15
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Miron RJ, Shuang Y, Sculean A, Buser D, Chandad F, Zhang Y. Gene array of PDL cells exposed to Osteogain in combination with a bone grafting material. Clin Oral Investig 2016; 20:2037-2043. [DOI: 10.1007/s00784-015-1702-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 12/28/2015] [Indexed: 01/31/2023]
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16
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Toyoda K, Fukuda T, Sanui T, Tanaka U, Yamamichi K, Atomura R, Maeda H, Tomokiyo A, Taketomi T, Uchiumi T, Nishimura F. Grp78 Is Critical for Amelogenin-Induced Cell Migration in a Multipotent Clonal Human Periodontal Ligament Cell Line. J Cell Physiol 2015; 231:414-27. [DOI: 10.1002/jcp.25087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 06/30/2015] [Indexed: 01/28/2023]
Affiliation(s)
- Kyosuke Toyoda
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Takao Fukuda
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Terukazu Sanui
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Urara Tanaka
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Kensuke Yamamichi
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Ryo Atomura
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
| | - Hidefumi Maeda
- Department of Endodontology; Kyushu University Hospital; Fukuoka Japan
| | - Atsushi Tomokiyo
- Department of Endodontology; Kyushu University Hospital; Fukuoka Japan
| | - Takaharu Taketomi
- Dental and Oral Medical Center; Kurume University School of Medicine; Kurume, Fukuoka Japan
| | - Takeshi Uchiumi
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences; Kyushu University; Fukuoka Japan
| | - Fusanori Nishimura
- Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science; Kyushu University; Fukuoka Japan
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17
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Wyganowska-Świątkowska M, Urbaniak P, Nohawica MM, Kotwicka M, Jankun J. Enamel matrix proteins exhibit growth factor activity: A review of evidence at the cellular and molecular levels. Exp Ther Med 2015; 9:2025-2033. [PMID: 26161150 DOI: 10.3892/etm.2015.2414] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 03/25/2015] [Indexed: 01/23/2023] Open
Abstract
Enamel matrix derivative (EMD) is a commercially available protein extract, mainly comprising amelogenins. A number of other polypeptides have been identified in EMD, mostly growth factors, which promote cementogenesis and osteogenesis during the regeneration processes through the regulation of cell proliferation, differentiation and activity; however, not all of their functions are clear. Enamel extracts have been proposed to have numerous activities such as bone morphogenetic protein- and transforming growth factor β (TGF-β)-like activity, and activities similar to those of insulin-like growth factor, fibroblast growth factor, platelet-derived growth factor, vascular endothelial growth factor and epidermal growth factor. These activities have been observed at the molecular and cellular levels and in numerous animal models. Furthermore, it has been suggested that EMD contains an unidentified biologically active factor that acts in combination with TGF-β1, and several studies have reported functional similarities between growth factors and TGF-β in cellular processes. The effects of enamel extracts on the cell cycle and biology are summarized and discussed in this review.
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Affiliation(s)
| | - Paulina Urbaniak
- Department of Cell Biology, Poznan University of Medical Sciences, Poznań 60-806, Poland
| | | | - Małgorzata Kotwicka
- Department of Cell Biology, Poznan University of Medical Sciences, Poznań 60-806, Poland
| | - Jerzy Jankun
- Department of Urology, Urology Research Centre, College of Medicine, University of Toledo, Toledo, OH 43614, USA ; Protein Research Chair, Department of Biochemistry, College of Sciences, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia ; Department of Clinical Nutrition, Medical University of Gdańsk, Gdańsk 80-211, Poland
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18
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Heng NH, Zahlten J, Cordes V, Ong MMA, Goh BT, N’Guessan PD, Pischon N. Effects of Enamel Matrix Derivative and Transforming Growth Factor-β1 on Connective Tissue Growth Factor in Human Periodontal Ligament Fibroblasts. J Periodontol 2015; 86:569-77. [DOI: 10.1902/jop.2015.120448] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Villa O, Brookes SJ, Thiede B, Heijl L, Lyngstadaas SP, Reseland JE. Subfractions of enamel matrix derivative differentially influence cytokine secretion from human oral fibroblasts. J Tissue Eng 2015; 6:2041731415575857. [PMID: 26090085 PMCID: PMC4456328 DOI: 10.1177/2041731415575857] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/09/2015] [Indexed: 01/09/2023] Open
Abstract
Enamel matrix derivative is used to promote periodontal regeneration during the corrective phase of the treatment of periodontal defects. Our main goal was to analyze the bioactivity of different molecular weight fractions of enamel matrix derivative. Enamel matrix derivative, a complex mixture of proteins, was separated into 13 fractions using size-exclusion chromatography and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and liquid chromatography-electrospray ionization-tandem mass spectrometry. Human periodontal ligament fibroblasts were treated with either enamel matrix derivative or the different fractions. Proliferation and cytokine secretion to the cell culture medium were measured and compared to untreated cells. The liquid chromatography-electrospray ionization-tandem mass spectrometry analyses revealed that the most abundant peptides were amelogenin and leucine-rich amelogenin peptide related. The fractions containing proteins above 20 kDa induced an increase in vascular endothelial growth factor and interleukin-6 secretion, whereas lower molecular weight fractions enhanced proliferation and secretion of interleukin-8 and monocyte chemoattractant protein-1 and reduced interleukin-4 release. The various molecular components in the enamel matrix derivative formulation might contribute to reported effects on tissue regeneration through their influence on vascularization, the immune response, and chemotaxis.
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Affiliation(s)
- Oscar Villa
- Department of Biomaterials, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Steven J Brookes
- Department of Oral Biology, School of Dentistry, University of Leeds, Leeds, UK
| | - Bernd Thiede
- The Biotechnology Centre of Oslo, University of Oslo, Oslo, Norway
| | | | - Staale P Lyngstadaas
- Department of Biomaterials, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Janne E Reseland
- Department of Biomaterials, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway
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20
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Nokhbehsaim M, Keser S, Nogueira AVB, Jäger A, Jepsen S, Cirelli JA, Bourauel C, Eick S, Deschner J. Leptin effects on the regenerative capacity of human periodontal cells. Int J Endocrinol 2014; 2014:180304. [PMID: 25136363 PMCID: PMC4129942 DOI: 10.1155/2014/180304] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/26/2014] [Accepted: 07/04/2014] [Indexed: 01/10/2023] Open
Abstract
Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactive molecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL) cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGFβ1, and VEGFA) and transcription (RUNX2) factors as well as matrix molecules (collagen, and periostin) and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.
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Affiliation(s)
- Marjan Nokhbehsaim
- Experimental Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
| | - Sema Keser
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
| | - Andressa Vilas Boas Nogueira
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Diagnosis and Surgery, School of Dentistry, UNESP, 14801-903 Araraquara, SP, Brazil
| | - Andreas Jäger
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Orthodontics, University of Bonn, 53111 Bonn, Germany
| | - Søren Jepsen
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
| | - Joni Augusto Cirelli
- Department of Diagnosis and Surgery, School of Dentistry, UNESP, 14801-903 Araraquara, SP, Brazil
| | - Christoph Bourauel
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Oral Technology, Center of Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
| | - Sigrun Eick
- Department of Periodontology, Laboratory of Oral Microbiology, University of Bern, 3010 Bern, Switzerland
| | - James Deschner
- Experimental Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
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21
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Nokhbehsaim M, Keser S, Nogueira AVB, Cirelli JA, Jepsen S, Jäger A, Eick S, Deschner J. Beneficial effects of adiponectin on periodontal ligament cells under normal and regenerative conditions. J Diabetes Res 2014; 2014:796565. [PMID: 25121107 PMCID: PMC4120919 DOI: 10.1155/2014/796565] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/24/2014] [Accepted: 06/25/2014] [Indexed: 01/24/2023] Open
Abstract
Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-α expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.
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Affiliation(s)
- Marjan Nokhbehsaim
- Experimental Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
| | - Sema Keser
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
| | - Andressa Vilas Boas Nogueira
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Diagnosis and Surgery, School of Dentistry, UNESP, 14801-903 Araraquara, SP, Brazil
| | - Joni Augusto Cirelli
- Department of Diagnosis and Surgery, School of Dentistry, UNESP, 14801-903 Araraquara, SP, Brazil
| | - Søren Jepsen
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
| | - Andreas Jäger
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
- Department of Orthodontics, University of Bonn, 53111 Bonn, Germany
| | - Sigrun Eick
- Department of Periodontology, Laboratory of Oral Microbiology, University of Bern, 3010 Bern, Switzerland
| | - James Deschner
- Experimental Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, University of Bonn, 53111 Bonn, Germany
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22
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Goda S, Inoue H, Takeuchi O, Ujii Y, Domae E, Ikeo T. Enamel matrix derivative protein enhances production of matrixmetalloproteinase-2 by osteoblasts. BMC Oral Health 2014; 14:85. [PMID: 25011999 PMCID: PMC4115475 DOI: 10.1186/1472-6831-14-85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/06/2014] [Indexed: 11/29/2022] Open
Abstract
Background Matrix metalloproteinases (MMPs) degrade the extracellular matrix (ECM) and regulate remodeling and regeneration of bone. Enamel matrix derivative (EMD) protein has been used clinically for periodontal regeneration, although its molecular mechanisms are not clear. We evaluated the role of matrix metalloproteinases (MMPs) in regulating EMD-dependent degradation of gelatin on oeoblast-like cell line MG63. Methods MG-63 cells (osteoblast cell line) were incubated with 100 μg/ml EMD protein in the presence or absence of MMP-2 tissue inhibitor for 20 h followed by incubation on DQ-gelatin-coated plates for 4 h. MG-63 cells (1 × 106) were preincubated with SB203580 for 30 min at 37°C and were then placed in 100 μg/ml EMD protein for 24 h. Conditioned media were collected and detected by Western blot analysis. Results EMD protein enhanced cell-mediated degradation of gelatin, which was inhibited by the MMP inhibitor TIMP-2. Furthermore, MMP-2 was produced by MG63 cells in response to EMD protein in a P38 MAPK-dependent manner. In addition, blocking of p38 MAPK activation by SB203580 significantly inhibited generation of the active form of MMP-2. Conclusion P38 MAPK pathway promotes expression MMP-2 in EMD activated osteoblasts, which in turn stimulates periodontal regeneration by degrading matrix proteins in periodontal connective tissue.
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Affiliation(s)
- Seiji Goda
- Department of Biochemistry, Osaka Dental University, Osaka, Japan.
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Wu SM, Chiu HC, Chin YT, Lin HY, Chiang CY, Tu HP, Fu MMJ, Fu E. Effects of enamel matrix derivative on the proliferation and osteogenic differentiation of human gingival mesenchymal stem cells. Stem Cell Res Ther 2014; 5:52. [PMID: 24739572 PMCID: PMC4076631 DOI: 10.1186/scrt441] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 01/28/2014] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Gingiva-derived mesenchymal stem cells (GMSCs) have recently been harvested and applied for rebuilding lost periodontal tissue. Enamel matrix derivative (EMD) has been used for periodontal regeneration and the formation of new cementum with inserting collagen fibers; however, alveolar bone formation is minimal. Recently, EMD has been shown to enhance the proliferation and mineralization of human bone marrow mesenchymal stem cells. Because the gingival flap is the major component to cover the surgical wound, the effects of EMD on the proliferation and mineralization of GMSCs were evaluated in the present study. METHODS After single cell suspension, the GMSCs were isolated from the connective tissues of human gingiva. The colony forming unit assay of the isolated GMSCs was measured. The expression of stem cell markers was examined by flow cytometry. The cellular telomerase activity was identified by polymerase chain reaction (PCR). The osteogenic, adipogenic and neural differentiations of the GMSCs were further examined. The cell proliferation was determined by MTS assay, while the expression of mRNA and protein for mineralization (including core binding factor alpha, cbfα-1; alkaline phosphatase, ALP; and osteocalcin, OC; ameloblastin, AMBN) were analyzed by real time-PCR, enzyme activity and confocal laser scanning microscopy. RESULTS The cell colonies could be easily identified and the colony forming rates and the telomerase activities increased after passaging. The GMSCs expressed high levels of surface markers for CD73, CD90, and CD105, but showed low expression of STRO-1. Osteogenic, adipogenic and neural differentiations were successfully induced. The proliferation of GMSCs was increased after EMD treatment. ALP mRNA was significantly augmented by treating with EMD for 3 hours, whereas AMBN mRNA was significantly increased at 6 hours after EMD treatment. The gene expression of OC was enhanced at the dose of 100 μg/ml EMD at day 3. Increased protein expression for cbfα-1 at day 3, for ALP at day 5 and 7, and for OC at week 4 after the EMD treatments were observed. CONCLUSIONS Human GMSCs could be successfully isolated and identified. EMD treatments not only induced the proliferation of GMSCs but also enhanced their osteogenic differentiation after induction.
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Iwata T, Yamato M, Ishikawa I, Ando T, Okano T. Tissue engineering in periodontal tissue. Anat Rec (Hoboken) 2013; 297:16-25. [PMID: 24343910 DOI: 10.1002/ar.22812] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 12/24/2022]
Abstract
Periodontitis, a recognized disease worldwide, is bacterial infection-induced inflammation of the periodontal tissues that results in loss of alveolar bone. Once it occurs, damaged tissue cannot be restored to its original form, even if decontaminating treatments are performed. For more than half a century, studies have been conducted to investigate true periodontal regeneration. Periodontal regeneration is the complete reconstruction of the damaged attachment apparatus, which contains both hard tissue (alveolar bone and cementum) and soft tissue (periodontal ligament). Several treatments, including bone grafts, guided tissue regeneration with physical barriers for epithelial cells, and growth factors have been approved for clinical use; however, their indications and outcomes are limited. To overcome these limitations, the concept of "tissue engineering" was introduced. Combination treatment using cells, growth factors, and scaffolds, has been studied in experimental animal models, and some studies have been translated into clinical trials. In this review, we focus on recent progressive tissue engineering studies and discuss future perspectives on periodontal regeneration.
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Affiliation(s)
- Takanori Iwata
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan; Department of Oral and Maxillofacial Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan
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Nokhbehsaim M, Keser S, Jäger A, Jepsen S, Deschner J. Regulation of regenerative periodontal healing by NAMPT. Mediators Inflamm 2013; 2013:202530. [PMID: 24288440 PMCID: PMC3830893 DOI: 10.1155/2013/202530] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/30/2013] [Accepted: 09/13/2013] [Indexed: 12/22/2022] Open
Abstract
Periodontitis is an inflammatory disease characterized by destruction of the tooth-supporting tissues. Obese individuals have an increased risk of periodontitis, and elevated circulating levels of nicotinamide phosphoribosyltransferase (NAMPT) may be a pathomechanistic link between both diseases. Recently, increased levels of NAMPT have also been found in patients with periodontitis, irrespective of the presence of obesity. This in vitro study sought to examine the effects of NAMPT on the regenerative capacity of human periodontal ligament (PDL) cells and, thereby, periodontal healing. PDL cells treated with enamel matrix derivative (EMD), which was used to mimic regenerative healing conditions in vitro, were grown in the presence and absence of NAMPT for up to 14 d. EMD stimulated significantly (P < 0.05) the expression of growth factors and their receptors, matrix molecules, osteogenesis-associated factors, and wound closure and calcium accumulation. In the presence of NAMPT, all these stimulatory effects were significantly (P < 0.05) reduced. In conclusion, the beneficial effects of EMD on a number of PDL cell functions critical for periodontal regeneration are counteracted by NAMPT. Enhanced levels of NAMPT, as found in obesity and periodontal inflammation, may compromise the regenerative capacity of PDL cells and, thereby, periodontal healing in the presence of EMD.
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Affiliation(s)
- Marjan Nokhbehsaim
- Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany
| | - Sema Keser
- Clinical Research Unit 208, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany
| | - Andreas Jäger
- Clinical Research Unit 208, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany
- Department of Orthodontics, University of Bonn, 53111 Bonn, Germany
| | - Søren Jepsen
- Clinical Research Unit 208, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
| | - James Deschner
- Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, 53111 Bonn, Germany
- Clinical Research Unit 208, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany
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Olivares-Navarrete R, Hyzy SL, Almaguer-Flores A, Mauth C, Gemperli AC, Boyan BD, Schwartz Z. Amelogenin Peptide Extract Increases Differentiation and Angiogenic and Local Factor Production and Inhibits Apoptosis in Human Osteoblasts. ACTA ACUST UNITED AC 2013. [DOI: 10.5402/2013/347318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Enamel matrix derivative (EMD), a decellularized porcine extracellular matrix (ECM), is used clinically in periodontal tissue regeneration. Amelogenin, EMD’s principal component, spontaneously assembles into nanospheres in vivo, forming an ECM complex that releases proteolytically cleaved peptides. However, the role of amelogenin or amelogenin peptides in mediating osteoblast response to EMD is not clear. Human MG63 osteoblast-like cells or normal human osteoblasts were treated with recombinant human amelogenin or a 5 kDa tyrosine-rich amelogenin peptide (TRAP) isolated from EMD and the effect on osteogenesis, local factor production, and apoptosis assessed. Treated MG63 cells increased alkaline phosphatase specific activity and levels of osteocalcin, osteoprotegerin, prostaglandin E2, and active/latent TGF-β1, an effect sensitive to the effector and concentration. Primary osteoblasts exhibited similar, but less robust, effects. TRAP-rich 5 kDa peptides yielded more mineralization than rhAmelogenin in osteoblasts in vitro. Both amelogenin and 5 kDa peptides protected MG63s from chelerythrine-induced apoptosis. The data suggest that the 5 kDa TRAP-rich sequence is an active amelogenin peptide that regulates osteoblast differentiation and local factor production and prevents osteoblast apoptosis.
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Affiliation(s)
- Rene Olivares-Navarrete
- School of Engineering, Virginia Commonwealth University, 601 West Main Street, Suite 331, Richmond, VA 23284-3068, USA
| | - Sharon L. Hyzy
- School of Engineering, Virginia Commonwealth University, 601 West Main Street, Suite 331, Richmond, VA 23284-3068, USA
| | - Argelia Almaguer-Flores
- Facultad de Odontologia, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Coyoacán, 04510 DF, Mexico
| | - Corinna Mauth
- Institut Straumann AG, Nauenstrasse, 4052 Basel, Switzerland
| | | | - Barbara D. Boyan
- School of Engineering, Virginia Commonwealth University, 601 West Main Street, Suite 331, Richmond, VA 23284-3068, USA
| | - Zvi Schwartz
- School of Engineering, Virginia Commonwealth University, 601 West Main Street, Suite 331, Richmond, VA 23284-3068, USA
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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Miron RJ, Bosshardt DD, Gemperli AC, Dard M, Buser D, Gruber R, Sculean A. In vitro characterization of a synthetic calcium phosphate bone graft on periodontal ligament cell and osteoblast behavior and its combination with an enamel matrix derivative. Clin Oral Investig 2013; 18:443-51. [DOI: 10.1007/s00784-013-0977-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 04/04/2013] [Indexed: 10/26/2022]
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Miron RJ, Bosshardt DD, Laugisch O, Dard M, Gemperli AC, Buser D, Gruber R, Sculean A. In vitro evaluation of demineralized freeze-dried bone allograft in combination with enamel matrix derivative. J Periodontol 2013; 84:1646-54. [PMID: 23347347 DOI: 10.1902/jop.2013.120574] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Preclinical and clinical studies suggest that a combination of enamel matrix derivative (EMD) with demineralized freeze-dried bone allograft (DFDBA) may improve periodontal wound healing and regeneration. To date, no single study has characterized the effects of this combination on in vitro cell behavior. The aim of this study is to test the ability of EMD to adsorb to the surface of DFDBA particles and determine the effect of EMD coating on downstream cellular pathways such as adhesion, proliferation, and differentiation of primary human osteoblasts and periodontal ligament (PDL) cells. METHODS DFDBA particles were precoated with EMD or human blood and analyzed for protein adsorption patterns via scanning electron microscopy. Cell attachment and proliferation were quantified using a commercial assay. Cell differentiation was analyzed using real-time polymerase chain reaction for genes encoding Runx2, alkaline phosphatase, osteocalcin, and collagen 1α1, and mineralization was assessed using alizarinred staining. RESULTS Analysis of cell attachment revealed no significant differences among control, blood-coated, and EMD-coated DFDBA particles. EMD significantly increased cell proliferation at 3 and 5 days after seeding for both osteoblasts and PDL cells compared to control and blood-coated samples. Moreover, there were significantly higher messenger ribonucleic acid levels of osteogenic differentiation markers, including collagen 1α1, alkaline phosphatase, and osteocalcin, in osteoblasts and PDL cells cultured on EMD-coated DFDBA particles at 3, 7, and 14 days. CONCLUSION The results suggest that the addition of EMD to DFDBA particles may influence periodontal regeneration by stimulating PDL cell and osteoblast proliferation and differentiation.
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Affiliation(s)
- Richard J Miron
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
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Maeda H, Wada N, Tomokiyo A, Monnouchi S, Akamine A. Prospective potency of TGF-β1 on maintenance and regeneration of periodontal tissue. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 304:283-367. [PMID: 23809439 DOI: 10.1016/b978-0-12-407696-9.00006-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Periodontal ligament (PDL) tissue, central in the periodontium, plays crucial roles in sustaining tooth in the bone socket. Irreparable damages of this tissue provoke tooth loss, causing a decreased quality of life. The question arises as to how PDL tissue is maintained or how the lost PDL tissue can be regenerated. Stem cells included in PDL tissue (PDLSCs) are widely accepted to have the potential to maintain or regenerate the periodontium, but PDLSCs are very few in number. In recent studies, undifferentiated clonal human PDL cell lines were developed to elucidate the applicable potentials of PDLSCs for the periodontal regenerative medicine based on cell-based tissue engineering. In addition, it has been suggested that transforming growth factor-beta 1 is an eligible factor for the maintenance and regeneration of PDL tissue.
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Affiliation(s)
- Hidefumi Maeda
- Department of Endodontology, Kyushu University Hospital, Fukuoka, Japan.
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Sakoda K, Nakajima Y, Noguchi K. Enamel matrix derivative induces production of vascular endothelial cell growth factor in human gingival fibroblasts. Eur J Oral Sci 2012; 120:513-9. [PMID: 23167467 DOI: 10.1111/j.1600-0722.2012.00999.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2012] [Indexed: 12/01/2022]
Abstract
Enamel matrix derivative (EMD) may enhance periodontal wound healing by inducing angiogenesis. We sought to investigate the effect and the mechanism of action of EMD on vascular endothelial growth factor (VEGF) production by human gingival fibroblasts. Cells were stimulated with EMD, transforming growth factor-β1 (TGF-β1), or fibroblast growth factor 2 (FGF-2), with or without antibodies to TGF-β1 or FGF-2. The levels of VEGF in the culture media were measured using an ELISA. We examined the effects of SB203580 [a p38 mitogen-activated protein kinase (MAPK) inhibitor], U0126 [an extracellular signal-regulated kinase (ERK) inhibitor], SP600125 [a c-Jun N-terminal kinase (JNK) inhibitor], and LY294002 [a phosphatidylinositol 3-kinase (PI3K)/Akt inhibitor] on EMD-induced VEGF production. Enamel matrix derivative stimulated the production of VEGF in a dose- and time-dependent manner. Treatment of human gingival fibroblasts with antibodies to TGF-β1 or FGF-2 significantly decreased EMD-induced VEGF production, whereas the addition of exogenous TGF-β1 and FGF-2 stimulated VEGF production. Enamel matrix derivative-induced VEGF production was significantly attenuated by SB203580, U0126, and LY294002. Our results suggest that EMD stimulates VEGF production partially via TGF-β1 and FGF-2 in human gingival fibroblasts and that EMD-induced VEGF production is regulated by ERK, p38 MAPK, and PI3K/Akt pathways. Enamel matrix derivative-induced production of VEGF by human gingival fibroblasts may be involved in the enhancement of periodontal wound healing by inducing angiogenesis.
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Affiliation(s)
- Kenji Sakoda
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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Lees JD, Robinson C, Shore RC, Paine ML, Brookes SJ. Cellular uptake and processing of enamel matrix derivative by human periodontal ligament fibroblasts. Arch Oral Biol 2012; 58:348-54. [PMID: 22939369 DOI: 10.1016/j.archoralbio.2012.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 07/18/2012] [Accepted: 08/05/2012] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Enamel matrix derivative (EMD), is an extract of porcine developing enamel matrix. Its commercialised form Emdogain, is claimed to stimulate periodontal regeneration by recapitulating original developmental processes, although the mechanism remains unclear. Our objective was to investigate interactions between EMD and human periodontal ligament (HPDL) fibroblasts in vitro. DESIGN HPDL fibroblasts were cultured in the presence of fluorescently labelled EMD and cellular EMD uptake was monitored using confocal laser scanning microscopy and immunohistochemistry. Internalised EMD proteins were characterised using SDS-PAGE. RESULTS EMD was internalised by HPDL fibroblasts leading to the appearance of multiple, vesicle-like structure in the cytoplasm. The internalised protein was composed mainly of the major 20kDa amelogenin component of EMD which was subsequently processed with time to generate a cumulative 5kDa component. CONCLUSIONS Cellular uptake and subsequent intracellular processing of EMD components by dental mesenchymal cells may play a role in EMD bioactivity and in part explain the turnover of Emdogain when placed clinically.
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Affiliation(s)
- James D Lees
- Department of Oral Biology, Leeds Dental Institute, University of Leeds, Leeds, England, United Kingdom
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Cheng L, Lin ZK, Shu R, Liu DL, Zhang XL, Liu B, Wang J, Tian L. Analogous effects of recombinant human full-length amelogenin expressed by Pichia pastoris yeast and enamel matrix derivative in vitro. Cell Prolif 2012; 45:456-65. [PMID: 22834823 DOI: 10.1111/j.1365-2184.2012.00834.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 04/09/2012] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVES Amelogenins are proposed to be responsible for enamel matrix derivative (EMD)-induced periodontal regeneration; however, heterogeneity of amelogenins makes it challenging to purify the full-length proteins. This study has been carried out to express and purify a recombinant full-length human amelogenin protein (rHhAm175) in the eukaryotic yeast Pichia pastoris, and further compare biological responses of human periodontal ligament fibroblasts (PDLFs) to rHhAm175 and porcine EMD (pEMD). MATERIALS AND METHODS Human cDNA encoding a 175-amino acid amelogenin was subcloned into the pPIC3.5K vector. The rHhAm175 expressed in P. pastoris GS115 (Mut+) was purified and characterized. We examined cell attachment, migration and proliferation responses of human PDLFs to rHhAm175 and pEMD respectively, and characterized associated changes of proliferation-related intracellular signalling molecules, including extracellular signal response kinase (ERK) and Akt kinases/protein kinase B (Akt/PKB) kinases. RESULTS The purified rHhAm175 was confirmed to be molecular mass 22 021.13 Da, phosphorylated human amelogenin, and alone significantly promoted proliferation and migration of human PDLFs to an extent comparable to that of pEMD. Cell attachment was increased over the first 60 min incubation with rHhAm175 or pEMD. Both rHhAm175 and pEMD induced PDLF mitogenesis via extracellular signal response kinase (ERK1/2), but not by Akt kinases/protein kinase B (Akt/PKB). CONCLUSIONS rHhAm175 modulated cell activities of human PDLFs, to a comparable extent as porcine EMD. These data suggest that rHhAm175 might be used to induce periodontal tissue regeneration.
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Affiliation(s)
- L Cheng
- Department of Periodontology, Shanghai Key Laboratory of Stomatology, 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Yan XZ, Rathe F, Gilissen C, van der Zande M, Veltman J, Junker R, Yang F, Jansen JA, Walboomers XF. The effect of enamel matrix derivative (Emdogain®) on gene expression profiles of human primary alveolar bone cells. J Tissue Eng Regen Med 2012; 8:463-72. [PMID: 22689476 DOI: 10.1002/term.1545] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 03/23/2012] [Accepted: 05/03/2012] [Indexed: 11/05/2022]
Abstract
Emdogain® is frequently used in regenerative periodontal treatment. Understanding its effect on gene expression of bone cells would enable new products and pathways promoting bone formation to be established. The aim of the study was to analyse the effect of Emdogain® on expression profiles of human-derived bone cells with the help of the micro-array, and subsequent validation. Bone was harvested from non-smoking patients during dental implant surgery. After outgrowth, cells were cultured until subconfluence, treated for 24 h with either Emdogain® (100 µg/ml) or control medium, and subsequently RNA was isolated and micro-array was performed. The most important genes demonstrated by micro-array data were confirmed by qPCR and ELISA tests. Emdogain tipped the balance between genes expressed for bone formation and bone resorption towards a more anabolic effect, by interaction of the PGE2 pathway and inhibition of IL-7 production. In addition the results of the present study indicate that Emdogain possibly has an effect on gene expression for extracellular matrix formation of human bone cells, in particular on bone matrix formation and on proliferation and differentiation. With the micro-array and the subsequent validation, the genes possibly involved in Emdogain action on bone cells were identified. These results can contribute to establishing new products and pathways promoting bone formation.
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Affiliation(s)
- X Z Yan
- Department of Biomaterials, Radboud University Nijmegen Medical Centre, The Netherlands
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Tanimoto K, Kunimatsu R, Tanne Y, Huang YC, Michida M, Yoshimi Y, Miyauchi M, Takata T, Tanne K. Differential Effects of Amelogenin on Mineralization of Cementoblasts and Periodontal Ligament Cells. J Periodontol 2012; 83:672-9. [DOI: 10.1902/jop.2011.110408] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Apical Periodontium Response to Enamel Matrix Derivative as an Intracanal Medication in Rat Immature Teeth with Pulp Necrosis: Radiographic and Histologic Findings. J Endod 2012; 38:449-53. [DOI: 10.1016/j.joen.2011.12.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Revised: 12/22/2011] [Accepted: 12/27/2011] [Indexed: 01/09/2023]
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Amin HD, Olsen I, Knowles JC, Donos N. Differential effect of amelogenin peptides on osteogenic differentiation in vitro: identification of possible new drugs for bone repair and regeneration. Tissue Eng Part A 2012; 18:1193-202. [PMID: 22320389 DOI: 10.1089/ten.tea.2011.0375] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Enamel matrix proteins (EMP) have been shown to promote regeneration of periodontal ligament and root cementum, and sometimes to enhance the differentiation of bone-forming cells in vitro and new bone growth in vivo. However, the inconsistent and unpredictable effects of EMP that have been reported for bone regeneration may be due to the highly variable composition of this heterogeneous material, which is comprised mainly of amelogenin and amelogenin-derived peptides. The present study has therefore examined the effects of naturally occurring low-molecular-weight (LMW) and high-molecular-weight (HMW) fractions of Emdogain(®) (EMD; Institut Straumann, Basel, Switzerland), a commercially available form of EMP, on osteogenic differentiation of bone precursor cells in vitro. In addition, the effects of chemically synthesized specific components of LMW and HMW-namely, the tyrosine-rich amelogenin peptide (TRAP), a specific amelogenin isoform derived by proteolytic clipping, and a leucine-rich amelogenin peptide (LRAP), an isoform derived by alternative splicing-on bone-forming cell activity were also investigated. Our findings demonstrate that while TRAP suppressed the formation of bone-like mineralized nodules, LRAP upregulated osteogenic differentiation. Furthermore, synthetically produced TRAP and its unique C-terminal 12 amino acid sequence (TCT) also suppressed bone-forming cells, whereas LRAP and its unique C-terminal 23 amino acid sequence (LCT) markedly enhanced terminal differentiation of bone-forming cells. These findings suggest that the differential effects of amelogenin-derived peptide sequences present in EMP could be of potential clinical value, with the novel bioactive TCT peptide as a useful tool for limiting pathological bone cell growth and the unique LCT sequence having therapeutic benefits in the treatment of periodontal and orthopedic diseases.
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Affiliation(s)
- Harsh D Amin
- Periodontology Unit, Department of Clinical Research, University College London, London, United Kingdom
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Wu T, Zhou H, Hong Y, Li J, Jiang X, Huang H. miR-30 family members negatively regulate osteoblast differentiation. J Biol Chem 2012; 287:7503-11. [PMID: 22253433 DOI: 10.1074/jbc.m111.292722] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
miRNAs are endogenously expressed 18- to 25-nucleotide RNAs that regulate gene expression through translational repression by binding to a target mRNA. Recently, it has been indicated that miRNAs are closely related to osteogenesis. Our previous data suggested that miR-30 family members might be important regulators during the biomineralization process. However, whether and how they modulate osteogenic differentiation have not been explored. In this study, we demonstrated that miR-30 family members negatively regulate BMP-2-induced osteoblast differentiation by targeting Smad1 and Runx2. Evidentially, overexpression of miR-30 family members led to a decrease of alkaline phosphatase activity, whereas knockdown of them increased the activity. Then bioinformatic analysis identified potential target sites of the miR-30 family located in the 3' untranslated regions of Smad1 and Runx2. Western blot analysis and quantitative RT-PCR assays demonstrated that miR-30 family members inhibit Smad1 gene expression on the basis of repressing its translation. Furthermore, dual-luciferase reporter assays confirmed that Smad1 is a direct target of miR-30 family members. Rescue experiments that overexpress Smad1 and Runx2 significantly eliminated the inhibitory effect of miR-30 on osteogenic differentiation and provided strong evidence that miR-30 mediates the inhibition of osteogenesis by targeting Smad1 and Runx2. Also, the inhibitory effects of the miR-30 family were validated in mouse bone marrow mesenchymal stem cells. Therefore, our study uncovered that miR-30 family members are key negative regulators of BMP-2-mediated osteogenic differentiation.
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Affiliation(s)
- Tingting Wu
- Department of Prosthodontics, Shanghai Key Laboratory of Stomatology, 639 Zhi Zaoju Road, Shanghai 200011, China
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Grandin HM, Gemperli AC, Dard M. Enamel matrix derivative: a review of cellular effects in vitro and a model of molecular arrangement and functioning. TISSUE ENGINEERING PART B-REVIEWS 2011; 18:181-202. [PMID: 22070552 DOI: 10.1089/ten.teb.2011.0365] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Enamel matrix derivative (EMD), the active component of Emdogain®, is a viable option in the treatment of periodontal disease owing to its ability to regenerate lost tissue. It is believed to mimic odontogenesis, though the details of its functioning remain the focus of current research. OBJECTIVE The aim of this article is to review all relevant literature reporting on the composition/characterization of EMD as well as the effects of EMD, and its components amelogenin and ameloblastin, on the behavior of various cell types in vitro. In this way, insight into the underlying mechanism of regeneration will be garnered and utilized to propose a model for the molecular arrangement and functioning of EMD. METHODS A review of in vitro studies of EMD, or components of EMD, was performed using key words "enamel matrix proteins" OR "EMD" OR "Emdogain" OR "amelogenin" OR "ameloblastin" OR "sheath proteins" AND "cells." Results of this analysis, together with current knowledge on the molecular composition of EMD and the structure and regulation of its components, are then used to present a model of EMD functioning. RESULTS Characterization of the molecular composition of EMD confirmed that amelogenin proteins, including their enzymatically cleaved and alternatively spliced fragments, dominate the protein complex (>90%). A small presence of ameloblastin has also been reported. Analysis of the effects of EMD indicated that gene expression, protein production, proliferation, and differentiation of various cell types are affected and often enhanced by EMD, particularly for periodontal ligament and osteoblastic cell types. EMD also stimulated angiogenesis. In contrast, EMD had a cytostatic effect on epithelial cells. Full-length amelogenin elicited similar effects to EMD, though to a lesser extent. Both the leucine-rich amelogenin peptide and the ameloblastin peptides demonstrated osteogenic effects. A model for molecular structure and functioning of EMD involving nanosphere formation, aggregation, and dissolution is presented. CONCLUSIONS EMD elicits a regenerative response in periodontal tissues that is only partly replicated by amelogenin or ameloblastin components. A synergistic effect among the various proteins and with the cells, as well as a temporal effect, may prove important aspects of the EMD response in vivo.
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Abstract
The role of regenerative periodontal therapy is the reconstitution of lost periodontal structures, ie, new formation of root cementum, periodontal ligament, and alveolar bone. The outcome of basic research has pointed to the important role of enamel matrix protein derivative (EMD) in periodontal wound healing. Histologic results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical studies have indicated that treatment with EMD positively influences periodontal wound healing in humans. The goal of this paper is to review the existing literature on EMD.
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Affiliation(s)
- Vandana J Rathva
- Department of Periodontics, KM Shah Dental College and Hospital, Sumandeep University, Gujarat, India
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Chan RC, Marino V, Bartold PM. The effect of Emdogain and platelet-derived growth factor on the osteoinductive potential of hydroxyapatite tricalcium phosphate. Clin Oral Investig 2011; 16:1217-27. [PMID: 22033661 DOI: 10.1007/s00784-011-0629-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 10/05/2011] [Indexed: 11/27/2022]
Abstract
The aim of this study was to determine whether hydroxyapatite β-tricalcium phosphate (HA-TCP) either alone or coated with Emdogain (EMD) or recombinant human platelet-derived growth factor-BB (rhPDGF-BB) becomes osteoinductive in the murine thigh muscle model for osteoinduction. Twenty CD1 adult male mice had gelatin capsules implanted into the thigh muscle of both hind limbs. The capsules were either empty or contained one of the following: uncoated particulate HA-TCP, EMD-coated HA-TCP or rhPDGF-BB-coated HA-TCP. The implant sites were assessed histologically at 4 and 8 weeks. A semi-quantitative histological examination was performed to assess the inflammatory changes, reparative processes and osteoinduction within the graft site. At both 4 and 8 weeks, histological analysis failed to demonstrate any osteoinductive activity in any of the specimens from the experimental groups. A minimal chronic inflammatory response and foreign body reaction around the implanted materials was seen which reduced over time. The HA-TCP particles were embedded within fibrous connective tissue and were encapsulated by a dense cellular layer consisting of active fibroblasts and occasional macrophages with the thickness of this layer decreasing over time. The results of this study suggest that the use of commercially available HA-TCP alone or in combination with EMD or rhPDGF-BB is biocompatible but not osteoinductive in the murine thigh muscle model of osteoinduction. Coating HA-TCP with EMD or rhPDGF-BB does not enhance its osteoinductive potential.
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Affiliation(s)
- R C Chan
- Colgate Australian Clinical Dental Research Centre, School of Dentistry, University of Adelaide, Frome Road, Adelaide, South Australia 5005, Australia
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A hybrid approach to direct pulp capping by using emdogain with a capping material. J Endod 2011; 37:667-72. [PMID: 21496668 DOI: 10.1016/j.joen.2011.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 01/29/2011] [Accepted: 02/03/2011] [Indexed: 11/20/2022]
Abstract
INTRODUCTION This study evaluated the formation of reparative hard tissues in baboon pulps after Emdogain (EMD) application in conjunction with 3 pulp-capping materials. METHODS Thirty-two premolars in four 3-year-old baboons were randomly assigned to 1 of 3 pulp-capping materials. A split-mouth design and intra-animal side randomization were applied to 3 experimental groups (calcium hydroxide, ProRoot White mineral trioxide aggregate, white Portland cement) and the control group (no pulp-capping material). In the hybrid EMD approach, a small drop of EMD was placed over the exposure site after arrest of hemorrhage. The designated pulp-capping material was placed over the EMD, followed by placement of resin-modified glass ionomer cement over the set/unset pulp-capping material. The animals were killed after 4 months. Histomorphometric analysis and micro-computed tomography were performed on the retrieved specimens. RESULTS All groups capped with EMD and 1 of the 3 capping materials exhibited similar reparative tissue thickness (P > .05). Dentin tunnel defects were absent in the mineral trioxide aggregate and Portland cement groups after the use of EMD. However, only a tubular was identified from all specimens. CONCLUSIONS Mineral trioxide aggregate produces a better quality reparative hard tissue response with the adjunctive use of Emdogain, when compared with the use of calcium hydroxide.
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Miron RJ, Hedbom E, Ruggiero S, Bosshardt DD, Zhang Y, Mauth C, Gemperli AC, Iizuka T, Buser D, Sculean A. Premature osteoblast clustering by enamel matrix proteins induces osteoblast differentiation through up-regulation of connexin 43 and N-cadherin. PLoS One 2011; 6:e23375. [PMID: 21858092 PMCID: PMC3156132 DOI: 10.1371/journal.pone.0023375] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 07/14/2011] [Indexed: 01/17/2023] Open
Abstract
In recent years, enamel matrix derivative (EMD) has garnered much interest in the dental field for its apparent bioactivity that stimulates regeneration of periodontal tissues including periodontal ligament, cementum and alveolar bone. Despite its widespread use, the underlying cellular mechanisms remain unclear and an understanding of its biological interactions could identify new strategies for tissue engineering. Previous in vitro research has demonstrated that EMD promotes premature osteoblast clustering at early time points. The aim of the present study was to evaluate the influence of cell clustering on vital osteoblast cell-cell communication and adhesion molecules, connexin 43 (cx43) and N-cadherin (N-cad) as assessed by immunofluorescence imaging, real-time PCR and Western blot analysis. In addition, differentiation markers of osteoblasts were quantified using alkaline phosphatase, osteocalcin and von Kossa staining. EMD significantly increased the expression of connexin 43 and N-cadherin at early time points ranging from 2 to 5 days. Protein expression was localized to cell membranes when compared to control groups. Alkaline phosphatase activity was also significantly increased on EMD-coated samples at 3, 5 and 7 days post seeding. Interestingly, higher activity was localized to cell cluster regions. There was a 3 fold increase in osteocalcin and bone sialoprotein mRNA levels for osteoblasts cultured on EMD-coated culture dishes. Moreover, EMD significantly increased extracellular mineral deposition in cell clusters as assessed through von Kossa staining at 5, 7, 10 and 14 days post seeding. We conclude that EMD up-regulates the expression of vital osteoblast cell-cell communication and adhesion molecules, which enhances the differentiation and mineralization activity of osteoblasts. These findings provide further support for the clinical evidence that EMD increases the speed and quality of new bone formation in vivo.
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Affiliation(s)
- Richard J Miron
- Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
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Kasaj A, Willershausen B, Junker R, Stratul SI, Schmidt M. Human periodontal ligament fibroblasts stimulated by nanocrystalline hydroxyapatite paste or enamel matrix derivative. An in vitro assessment of PDL attachment, migration, and proliferation. Clin Oral Investig 2011; 16:745-54. [DOI: 10.1007/s00784-011-0570-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Accepted: 05/17/2011] [Indexed: 11/30/2022]
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Nokhbehsaim M, Deschner B, Winter J, Bourauel C, Rath B, Jäger A, Jepsen S, Deschner J. Interactions of regenerative, inflammatory and biomechanical signals on bone morphogenetic protein-2 in periodontal ligament cells. J Periodontal Res 2011; 46:374-81. [PMID: 21410703 DOI: 10.1111/j.1600-0765.2011.01357.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND OBJECTIVE Regeneration of periodontal tissues by EMD remains a major challenge because a number of modifying factors are as yet unknown. The effects of EMD seem to be mediated, at least in part, by bone morphogenetic protein-2 (BMP-2). This in vitro study was performed to examine whether the effects of EMD on BMP-2 activity are modulated by inflammatory and/or biomechanical signals. MATERIAL AND METHODS Periodontal ligament cells were seeded on BioFlex(®) plates and exposed to EMD under normal, inflammatory or biomechanical loading conditions for 1 and 6 d. In order to mimic proinflammatory or biomechanical loading conditions in vitro, cells were stimulated with interleukin-1β (IL-1β), which is increased at inflamed periodontal sites, and cyclic tensile strain of various magnitudes, respectively. The synthesis of BMP-2, its receptors (BMPR-1A, BMPR-1B and BMPR-2) and its inhibitors (follistatin, matrix gla protein and noggin) were analyzed using real-time RT-PCR and ELISA. RESULTS In EMD-treated cells, BMP-2 synthesis was increased significantly at 1 d. EMD also induced the expression of all BMP receptors, and of the BMP inhibitors follistatin and noggin. In general, IL-1β and biomechanical loading neither down-regulated BMP-2 nor up-regulated BMP inhibitors in EMD-stimulated cells. However, IL-1β and biomechanical loading, when applied for a longer time period, caused a down-regulation of EMD-induced BMP receptors. CONCLUSION EMD induces not only BMP-2, but also its receptors and inhibitors, in PDL cells. IL-1β and biomechanical forces may counteract the beneficial effects of EMD on BMP-2 activity via the down-regulation of BMP receptors.
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Affiliation(s)
- M Nokhbehsaim
- Clinical Research Unit, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
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The effect of enamel matrix protein on gingival tissue thickness in vivo. Odontology 2011; 100:61-6. [DOI: 10.1007/s10266-011-0022-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 12/28/2010] [Indexed: 11/30/2022]
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Silvestri M, Rasperini G, Milani S. 120 Infrabony Defects Treated With Regenerative Therapy: Long-Term Results. J Periodontol 2011; 82:668-75. [DOI: 10.1902/jop.2010.100297] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kunimatsu R, Tanimoto K, Tanne Y, Kamiya T, Ohkuma S, Huang YC, Yoshimi Y, Miyauchi M, Takata T, Tanne K. Amelogenin enhances the proliferation of cementoblast lineage cells. J Periodontol 2011; 82:1632-8. [PMID: 21486179 DOI: 10.1902/jop.2011.110031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND It is well known that enamel matrix proteins play a crucial role in tooth root formation and amelogenesis. Because amelogenin is a major enamel matrix protein, it is assumed that amelogenin also affects the metabolism of cementum. However, the biologic functions of amelogenin in cementoblasts remain unclear. The purpose of this study is to examine the effect of recombinant human full-length amelogenin (rh174) on the proliferation of cultured human cementoblast-like (HCEM) and human periodontal ligament (HPDL) cells. METHODS HCEM and HPDL cells were cultured and treated with 100 ng/mL rh174 in the presence or absence of an anti-cluster of differentiation (CD) 63 blocking antibody. Cell proliferation was evaluated using a cell proliferation enzyme-linked immunosorbent assay 5-bromo-2-deoxyuridine kit and quantification of the cell number by 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium-inner salt assay. The phosphorylation of extracellular signal-regulated kinases (ERK) 1/2 was measured by enzyme-linked immunosorbent assay and Western blot analysis. RESULTS The proliferation of HCEM and HPDL cells was enhanced significantly (P <0.05) by treatment with rh174, and inhibited significantly (P <0.05) by the addition of anti-CD63 blocking antibody. In addition, the ratio of phosphorylated ERK1/2 to total ERK1/2 became significantly larger (P <0.05) by treatment with rh174, and was reduced significantly by the addition of anti-CD63 blocking antibody in both HCEM and HPDL cells. CONCLUSION The results show that rh174 interacts with CD63, and rh174/CD63 interaction activates the ERK1/2 signaling pathway, enhancing the proliferation activities of HCEM and HPDL cells.
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Affiliation(s)
- Ryo Kunimatsu
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan
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Nokhbehsaim M, Deschner B, Bourauel C, Reimann S, Winter J, Rath B, Jäger A, Jepsen S, Deschner J. Interactions of enamel matrix derivative and biomechanical loading in periodontal regenerative healing. J Periodontol 2011; 82:1725-34. [PMID: 21513471 DOI: 10.1902/jop.2011.100678] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Although enamel matrix derivative (EMD) has been shown to promote periodontal regeneration, it is unknown whether the actions of EMD are modulated by occlusal loading. This in vitro study was performed to investigate whether biomechanical forces regulate the response of periodontal ligament (PDL) cells to EMD. METHODS Human PDL cells were treated with EMD in the presence and absence of cyclic tensile strain (CTS) of various magnitudes for ≤ 14 days. Synthesis of transforming growth factor (TGF)-β1, vascular endothelial growth factor (VEGF), growth factor receptors, collagen, and runt-related transcription factor 2- (RUNX2), cell numbers and adhesion, wound fill rate, and calcium accumulation were analyzed by real-time polymerase chain reaction, enzyme-linked immunosorbent assay, a wound healing assay, and alizarine red S staining. RESULTS Wound fill rate, cell numbers and adhesion, and expression of TGF-β1, VEGF, collagen, and RUNX2 were significantly increased by EMD. In the presence of CTS, the EMD-induced effects were significantly reduced. The inhibition of the EMD-upregulated VEGF expression by CTS was blocked by a specific inhibitor of nuclear factor-kappa B signaling. Moreover, CTS downregulated receptors for growth factors involved in the actions of EMD. CTS also antagonized significantly the EMD-induced calcium deposition. CONCLUSIONS These in vitro findings suggest that the beneficial actions of EMD on PDL cell functions critical for periodontal regeneration are jeopardized by biomechanical loading. Clinical studies should clarify whether protection of teeth against occlusal forces in the early healing stage may positively affect the outcome of regenerative therapy with EMD.
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Possibilities and potential roles of the functional peptides based on enamel matrix proteins in promoting the remineralization of initial enamel caries. Med Hypotheses 2011; 76:391-4. [DOI: 10.1016/j.mehy.2010.10.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 10/21/2010] [Accepted: 10/29/2010] [Indexed: 11/18/2022]
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Nokhbehsaim M, Winter J, Rath B, Jäger A, Jepsen S, Deschner J. Effects of enamel matrix derivative on periodontal wound healing in an inflammatory environment in vitro. J Clin Periodontol 2011; 38:479-90. [DOI: 10.1111/j.1600-051x.2010.01696.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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