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Aoki K, Ideta H, Komatsu Y, Tanaka A, Kito M, Okamoto M, Takahashi J, Suzuki S, Saito N. Bone-Regeneration Therapy Using Biodegradable Scaffolds: Calcium Phosphate Bioceramics and Biodegradable Polymers. Bioengineering (Basel) 2024; 11:180. [PMID: 38391666 PMCID: PMC10886059 DOI: 10.3390/bioengineering11020180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/01/2024] [Accepted: 02/08/2024] [Indexed: 02/24/2024] Open
Abstract
Calcium phosphate-based synthetic bone is broadly used for the clinical treatment of bone defects caused by trauma and bone tumors. Synthetic bone is easy to use; however, its effects depend on the size and location of the bone defect. Many alternative treatment options are available, such as joint arthroplasty, autologous bone grafting, and allogeneic bone grafting. Although various biodegradable polymers are also being developed as synthetic bone material in scaffolds for regenerative medicine, the clinical application of commercial synthetic bone products with comparable performance to that of calcium phosphate bioceramics have yet to be realized. This review discusses the status quo of bone-regeneration therapy using artificial bone composed of calcium phosphate bioceramics such as β-tricalcium phosphate (βTCP), carbonate apatite, and hydroxyapatite (HA), in addition to the recent use of calcium phosphate bioceramics, biodegradable polymers, and their composites. New research has introduced potential materials such as octacalcium phosphate (OCP), biologically derived polymers, and synthetic biodegradable polymers. The performance of artificial bone is intricately related to conditions such as the intrinsic material, degradability, composite materials, manufacturing method, structure, and signaling molecules such as growth factors and cells. The development of new scaffold materials may offer more efficient bone regeneration.
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Affiliation(s)
- Kaoru Aoki
- Physical Therapy Division, School of Health Sciences, Shinshu University, Matsumoto 390-8621, Japan
| | - Hirokazu Ideta
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Yukiko Komatsu
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Atsushi Tanaka
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Munehisa Kito
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Masanori Okamoto
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Jun Takahashi
- Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto 390-8621, Japan
| | - Shuichiro Suzuki
- Department of Orthopaedic Surgery, Matsumoto Medical Center, Matsumoto 390-8621, Japan
| | - Naoto Saito
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Matsumoto 390-8621, Japan
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Arias-Betancur A, Badilla-Wenzel N, Astete-Sanhueza Á, Farfán-Beltrán N, Dias FJ. Carrier systems for bone morphogenetic proteins: An overview of biomaterials used for dentoalveolar and maxillofacial bone regeneration. Jpn Dent Sci Rev 2022; 58:316-327. [PMID: 36281233 PMCID: PMC9587372 DOI: 10.1016/j.jdsr.2022.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 09/14/2022] [Accepted: 10/11/2022] [Indexed: 11/27/2022] Open
Abstract
Different types of biomaterials have been used to fabricate carriers to deliver bone morphogenetic proteins (BMPs) in both dentoalveolar and maxillofacial bone regeneration procedures. Despite that absorbable collagen sponge (ACS) is considered the gold standard for BMP delivery, there is still some concerns regarding its use mainly due to its poor mechanical properties. To overcome this, novel systems are being developed, however, due to the wide variety of biomaterial combination, the heterogeneous assessment of newly formed tissue, and the intended clinical applications, there is still no consensus regarding which is more efficient in a particular clinical scenario. The combination of two or more biomaterials in different topological configurations has allowed specific controlled-release patterns for BMPs, improving their biological and mechanical properties compared with classical single-material carriers. However, more basic research is needed. Since the BMPs can be used in multiple clinical scenarios having different biological and mechanical needs, novel carriers should be developed in a context-specific manner. Thus, the purpose of this review is to gather current knowledge about biomaterials used to fabricate delivery systems for BMPs in both dentoalveolar and maxillofacial contexts. Aspects related with the biological, physical and mechanical characteristics of each biomaterial are also presented and discussed. Strategies for bone formation and regeneration are a major concern in dentistry. Topical delivery of bone morphogenetic proteins (BMPs) allows rapid bone formation. BMPs requires proper carrier system to allow controlled and sustained release. Carrier should also fulfill mechanical requirements of bone defect sites. By using complex composites, it would be possible to develop new carriers for BMPs.
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Affiliation(s)
- Alain Arias-Betancur
- Department of Integral Adult Dentistry, Research Centre for Dental Sciences (CICO-UFRO), Dental School-Facultad de Odontología, Universidad de La Frontera, Temuco 4811230, Chile
| | - Nicolás Badilla-Wenzel
- Dental School-Facultad de Odontología, Universidad de La Frontera, Temuco 4811230, Chile
| | - Álvaro Astete-Sanhueza
- Dental School-Facultad de Odontología, Universidad de La Frontera, Temuco 4811230, Chile
| | - Nicole Farfán-Beltrán
- Department of Integral Adult Dentistry, Research Centre for Dental Sciences (CICO-UFRO), Dental School-Facultad de Odontología, Universidad de La Frontera, Temuco 4811230, Chile.,Universidad Adventista de Chile, Chillán 3780000, Chile
| | - Fernando José Dias
- Department of Integral Adult Dentistry, Oral Biology Research Centre (CIBO-UFRO), Dental School-Facultad de Odontología, Universidad de La Frontera, Temuco 4811230, Chile
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Pankongadisak P, Tsekoura E, Suwantong O, Uludağ H. Electrospun gelatin matrices with bioactive pDNA polyplexes. Int J Biol Macromol 2020; 149:296-308. [DOI: 10.1016/j.ijbiomac.2020.01.252] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/22/2020] [Accepted: 01/24/2020] [Indexed: 12/15/2022]
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Abstract
Regenerative medicine has been widely researched for the treatment of bone defects. In the field of bone regenerative medicine, signaling molecules and the use of scaffolds are of particular importance as drug delivery systems (DDS) or carriers for cell differentiation, and various materials have been explored for their potential use. Although calcium phosphates such as hydroxyapatite and tricalcium phosphate are clinically used as synthetic scaffold material for bone regeneration, biodegradable materials have attracted much attention in recent years for their clinical application as scaffolds due their ability to facilitate rapid localized absorption and replacement with autologous bone. In this review, we introduce the types, features, and performance characteristics of biodegradable polymer scaffolds in their role as DDS for bone regeneration therapy.
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Affiliation(s)
- Kaoru Aoki
- Physical Therapy Division, School of Health Sciences, Shinshu University, Asahi 3-1-1, Matsumoto, Nagano 390-8621, Japan;
| | - Naoto Saito
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Asahi 3-1-1, Matsumoto, Nagano 390-8621, Japan
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Agrawal V, Sinha M. A review on carrier systems for bone morphogenetic protein-2. J Biomed Mater Res B Appl Biomater 2016; 105:904-925. [PMID: 26728994 DOI: 10.1002/jbm.b.33599] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 12/01/2015] [Accepted: 12/03/2015] [Indexed: 01/26/2023]
Abstract
Bone morphogenetic protein-2 (BMP-2) has unique bone regeneration property. The powerful osteoinductive nature makes it considered as second line of therapy in nonunion bone defect. A large number of carriers and delivery systems made up of different materials have been investigated for controlled and sustained release of BMP-2. The delivery systems are in the form of hydrogel, microsphere, nanoparticles, and fibers. The carriers used for the delivery are made up of metals, ceramics, polymers, and composites. Implantation of these protein-loaded carrier leads to cell adhesion, degradation which eventually releases the drug/protein at site specific. But, problems like ectopic growth, lesser protein delivery, inactivation of the protein are reported in the available carrier systems. Therefore, it is need of an hour to modify the available carrier systems as well as explore other biomaterials with desired properties. In this review, all the reported carrier systems made of metals, ceramics, polymers, composites are evaluated in terms of their processing conditions, loading capacity and release pattern of BMP-2. Along with these biomaterials, the attempts of protein modification by adding some functional group to BMP-2 or extracting functional peptides from the protein to achieve the desired effect, is also evaluated. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 904-925, 2017.
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Affiliation(s)
- Vishal Agrawal
- Department of Medical Devices, National Institute of Pharmaceutical Education and Research-Ahmedabad, Ahmedabad-, 380054, India
| | - Mukty Sinha
- Department of Medical Devices, National Institute of Pharmaceutical Education and Research-Ahmedabad, Ahmedabad-, 380054, India
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Kim BR, Nguyen TBL, Min YK, Lee BT. In vitro and in vivo studies of BMP-2-loaded PCL-gelatin-BCP electrospun scaffolds. Tissue Eng Part A 2014; 20:3279-89. [PMID: 24935525 PMCID: PMC4259169 DOI: 10.1089/ten.tea.2014.0081] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 05/28/2014] [Indexed: 01/06/2023] Open
Abstract
To confirm the effect of recombinant human bone morphogenetic protein-2 (BMP-2) for bone regeneration, BMP-2-loaded polycaprolactone (PCL)-gelatin (Gel)-biphasic calcium phosphate (BCP) fibrous scaffolds were fabricated using the electrospinning method. The electrospinning process to incorporate BCP nanoparticles into the PCL-Gel scaffolds yielded an extracellular matrix-like microstructure that was a hybrid system composed of nano- and micro-sized fibers. BMP-2 was homogeneously loaded on the PCL-Gel-BCP scaffolds for enhanced induction of bone growth. BMP-2 was initially released at high levels, and then showed sustained release behavior for 31 days. Compared with the PCL-Gel-BCP scaffold, the BMP-2-loaded PCL-Gel-BCP scaffold showed improved cell proliferation and cell adhesion behavior. Both scaffold types were implanted in rat skull defects for 4 and 8 weeks to evaluate the biological response under physiological conditions. Remarkable bone regeneration was observed in the BMP-2/PCL-Gel-BCP group. These results suggest that BMP-2-loaded PCL-Gel-BCP scaffolds should be considered for potential bone tissue engineering applications.
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Affiliation(s)
- Bo-Ram Kim
- Department of Regenerative Medicine, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
| | - Thuy Ba Linh Nguyen
- Department of Regenerative Medicine, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
- Institute of Tissue Regeneration, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
| | - Young-Ki Min
- Institute of Tissue Regeneration, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
- Department of Physiology, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
| | - Byong-Taek Lee
- Department of Regenerative Medicine, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
- Institute of Tissue Regeneration, College of Medicine, Soonchunhyang University, Cheonan, Republic of Korea
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Félix Lanao RP, Jonker AM, Wolke JG, Jansen JA, van Hest JC, Leeuwenburgh SC. Physicochemical properties and applications of poly(lactic-co-glycolic acid) for use in bone regeneration. Tissue Eng Part B Rev 2013; 19:380-90. [PMID: 23350707 PMCID: PMC3690090 DOI: 10.1089/ten.teb.2012.0443] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 01/11/2013] [Indexed: 11/12/2022]
Abstract
Poly(lactic-co-glycolic acid) (PLGA) is the most often used synthetic polymer within the field of bone regeneration owing to its biocompatibility and biodegradability. As a consequence, a large number of medical devices comprising PLGA have been approved for clinical use in humans by the American Food and Drug Administration. As compared with the homopolymers of lactic acid poly(lactic acid) and poly(glycolic acid), the co-polymer PLGA is much more versatile with regard to the control over degradation rate. As a material for bone regeneration, the use of PLGA has been extensively studied for application and is included as either scaffolds, coatings, fibers, or micro- and nanospheres to meet various clinical requirements.
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Affiliation(s)
- Rosa P. Félix Lanao
- Department of Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Anika M. Jonker
- Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Joop G.C. Wolke
- Department of Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - John A. Jansen
- Department of Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Jan C.M. van Hest
- Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Sander C.G. Leeuwenburgh
- Department of Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
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Rotenberg SA, Tatakis DN. Recombinant Human Bone Morphogenetic Protein-2 for Peri-Implant Bone Regeneration: A Case Report. J Periodontol 2011; 82:1212-8. [DOI: 10.1902/jop.2011.100626] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Saito A, Saito E, Handa R, Honma Y, Kawanami M. Influence of residual bone on recombinant human bone morphogenetic protein-2-induced periodontal regeneration in experimental periodontitis in dogs. J Periodontol 2009; 80:961-8. [PMID: 19485827 DOI: 10.1902/jop.2009.080568] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Previous studies reported that bone morphogenetic protein (BMP)-2 induced periodontal regeneration in animals. However, the effects of local host factors on bone formation when using recombinant human (rh)BMP-2 are unknown. The purpose of this study was to evaluate local conditions in recipient sites that affected periodontal regeneration following BMP implantation in experimentally induced horizontal defects in dogs. METHODS Experimental periodontitis was induced in the maxillary and mandibular premolars of six male beagles. The recipient sites were divided into four quadrants (maxillary buccal, maxillary palatal, mandibular buccal, and mandibular lingual sites). A polymer-coated gelatin sponge (PGS; 3 x 3 x 2 mm) was impregnated with 7.2 mul rhBMP-2 solution. The recipient sites in each quadrant were treated with physiologic saline/PGS and rhBMP-2/PGS (rhBMP-2 at 7.2 mug/7.2 mul). The dogs were sacrificed 12 weeks post-surgery, and healing was evaluated histologically. RESULTS Bone formation and connective tissue attachment were observed following rhBMP-2/PGS implantation. In the four recipient sites of the BMP-treated group, significant positive correlations were found between the width of residual bone and the height and area of regenerated bone (r = 0.791; r = 0.828; P <0.0001). The height of regenerated bone was also significantly correlated to the area (r = 0.891; P <0.0001). CONCLUSIONS The width of residual bone was one of the clinical host factors that affected bone regeneration following BMP implantation. However, it did not affect connective tissue attachment, cementum regeneration, and downgrowth of junctional epithelium.
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Affiliation(s)
- Akira Saito
- Department of Periodontology and Endodontology, Division of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan.
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Kokubo S, Nozaki K, Fukushima S, Takahashi K, Miyata K, Fujimoto R, Yokota S. Recombinant Human Bone Morphogenetic Protein-2 as an Osteoinductive Biomaterial and a Biodegradable Carrier in a Rabbit Ulnar Defect Model. J BIOACT COMPAT POL 2008. [DOI: 10.1177/0883911508092791] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We investigated early local changes induced by recombinant human bone morphogenetic protein (rhBMP)-2 and a novel carrier, poly[L-lactide-co-glycolide] copolymer-coated gelatin sponge (PGS). A 1.5 cm segmental bone defect was created in the diaphysis of the right ulna of male Japanese white rabbit. Defects received PGS with or without rhBMP-2 (0, 0.4, or 1 mg/cm3) and were harvested at 3, 7, 14, 21, or 28 days post implantation for histological examination. Immuno-staining for vascular endothelial growth factor (VEGF) was also performed. Spindle-shaped cells were observed in the rhBMP-2-treated groups 3 and 7 days after implantation. Bone regeneration was detected after 14 days in the rhBMP-2-treated groups and the bone area increased with time and dose. Expression of VEGF was observed in all groups at 3 days and was maintained by 14 days only in the defects treated with rhBMP-2 at a dose of 1 mg. These results indicate that rhBMP-2 exert its osteo-inductive activities via the promotion of osteogenic cell mobilization, and possibly via angiogenesis based on VEGF induction. Foreign-body reactions to the implanted PGS were similar to those observed when either poly[L-lactide-co-glycolide] copolymer or gelatin was individually implanted. These results indicate that the PGS is a useful and safe carrier for rhBMP-2.
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Affiliation(s)
- Satoshi Kokubo
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd, 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan,
| | - Kazutoshi Nozaki
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd, 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan
| | - Shinji Fukushima
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd, 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan
| | - Koichiro Takahashi
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd, 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan
| | - Keiji Miyata
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd, 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan
| | - Ryuhei Fujimoto
- Institute for Drug Development Research, Yamanouchi Pharmaceutical Co., Ltd, 1-1-8 Azusawa, Itabashi-ku, Tokyo, 174-8511, Japan
| | - Shoji Yokota
- Institute for Drug Development Research, Yamanouchi Pharmaceutical Co., Ltd, 180 Ohzumi, Yaizu, Shizuoka, 425-0072, Japan
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Kawakatsu N, Oda S, Kinoshita A, Kikuchi S, Tsuchioka H, Akizuki T, Hayashi C, Kokubo S, Ishikawa I, Izumi Y. Effect of rhBMP-2 with PLGA/gelatin sponge type (PGS) carrier on alveolar ridge augmentation in dogs. J Oral Rehabil 2008; 35:647-55. [PMID: 18482353 DOI: 10.1111/j.1365-2842.2008.01850.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Recombinant human bone morphogenetic protein-2 has been shown to promote bone formation because of its osteoinductive property. The purpose of this study was to evaluate the efficacy of rhBMP-2 delivered on a poly (D, L-lactic-co-glycolic acid) copolymer/gelatin sponge (PGS) in vertical alveolar ridge augmentation on height-reduced edentulous mandible to verify the retention of rhBMP-2 withstanding the pressure of soft tissues. Coronal defects of the alveolar bone were created in six adult beagle dogs. After a healing period of 9 weeks, PGSs with or without rhBMP-2 (0 or 0.4 mg mL(-1)) were implanted on the defects(6 mm in height, 30 mm in length, 8 mm in width). Sixteen weeks after implantation, the bone mineral content (BMC) and the total bone area were measured by peripheral quantitative computed tomography. The BMC and the total bone area of the defect sites with rhBMP-2 group were significantly greater (133+/-33 mg mm(-1), 277+/-54 mm2, respectively) than those of the control group (80+/-19 mg mm(-1), 155+/-49 mm2, respectively) (P<0.01, P<0.0001, respectively; paired t-test). From the histological analyses, the height of newly formed bone in the experimental group was greater than that of the control group (4.3+/-0.9 mm, 0.22+/-0.28 mm, P<0.0001, n=6, paired t-test). These results indicate that PGS has characteristics of effective bone graft substitutes for implantation of rhBMP-2 on vertical alveolar ridge augmentation in huge defect of mandibles in dogs.
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Affiliation(s)
- N Kawakatsu
- Section of Periodontology, Department of Hard Tissue Engineering, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
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Shimazu C, Hara T, Kinuta Y, Moriya K, Maruo Y, Hanada S, Minagi S. Enhanced vertical alveolar bone augmentation by recombinant human bone morphogenetic protein-2 with a carrier in rats. J Oral Rehabil 2007; 33:609-18. [PMID: 16856959 DOI: 10.1111/j.1365-2842.2005.01593.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This study aimed to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on vertical bone regeneration of edentulous ridge. Bilateral upper first and second molars of 8-week-old Wistar rats were extracted and the ridges were allowed to heal for 3 weeks. Compressed poly(lactic-co-glycolic acid) copolymer/gelatin sponge (PGS) was used as a carrier of rhBMP-2. PGS alone (control group) or PGS with 5 mug rhBMP-2 (test group) was implanted at the top part of alveolar ridge. The sham group received no implantation. The rats were killed at 1, 2, 4, 8 and 12 weeks after implantation and examined histologically and histomorphometrically. In the test group, significant bone augmentation was evident on the alveolar ridge throughout the experimental period. Histomorphometric analysis revealed greater tissue volume and height of alveolar bone in the test group compared with the control and sham groups (P < 0.05) from 4 weeks onward and the augmented tissues (5 mm3 in tissue volume and 1.5 mm in bone height) were maintained until 12 weeks. Osteoblast surface increased at 2 and 4 weeks and osteoid thickness reached a peak (25 microm) at 2 weeks. Dynamic variables, which represented calcification, were higher in the test group than the control and sham groups at 4 and 8 weeks (P < 0.05). These results suggest that use of rhBMP-2/PGS may achieve vertical bone augmentation, and stabilizes denture prosthesis or makes up for inadequate bone mass for implant prosthesis.
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Affiliation(s)
- C Shimazu
- Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine and Dentistry, Okayama City, Japan
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Someya A, Yuyama H, Fujimori A, Ukai M, Fukushima S, Sasamata M. Effect of YM598, a selective endothelin ETA receptor antagonist, on endothelin-1-induced bone formation. Eur J Pharmacol 2006; 543:14-20. [PMID: 16843458 DOI: 10.1016/j.ejphar.2006.06.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2006] [Revised: 06/16/2006] [Accepted: 06/19/2006] [Indexed: 01/08/2023]
Abstract
We investigated the effect of endothelin-1 on bone formation in vitro and in vivo, and the effect of YM598, a novel selective endothelin ET(A) receptor antagonist, on endothelin-1-induced responses. In in vitro studies, the effect of endothelin-1 on cellular responses was investigated by measuring intracellular Ca(2+) levels, cell growth and alkaline phosphatase activity in the mouse osteoblast-like cell line MC3T3-E1. In in vivo studies, the effect of endothelin-1 on bone morphogenetic protein-2-induced ectopic bone formation in rats was investigated. A carrier containing bone morphogenetic protein-2 with or without endothelin-1 was subcutaneously implanted over the thorax, and the tissue (carrier) calcium content 3 weeks after implantation was evaluated. The inhibitory effect of YM598 on these responses was also investigated. In the in vitro studies, endothelin-1 (10(-13) to 10(-6) M) significantly increased intracellular Ca(2+) concentration, DNA synthesis and cell number in a concentration-dependent manner, while significantly decreasing alkaline phosphatase activity. YM598 (10(-12) to 10(-4) M) significantly inhibited these increases, as well as the decrease in alkaline phosphatase activity, in a concentration-dependent manner. In the in vivo studies, the tissue calcium content 3 weeks after carrier implantation was significantly higher in the group that received both bone morphogenetic protein-2 and endothelin-1 than in the group receiving bone morphogenetic protein-2 alone. Chronically administered YM598 (1 mg/kg/day) marginally inhibited this endothelin-1-potentiated ectopic bone formation. These results suggest that endothelin-1 may induce bone formation via endothelin ET(A) receptors in vitro and in vivo.
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Affiliation(s)
- Akiyoshi Someya
- Pharmacology Laboratories, Institute for Drug Discovery Research, Astellas Pharma, Inc. 21, Miyukigaoka, Tsukuba-shi, Ibaraki 305-8585, Japan.
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Tanaka E, Ishino Y, Sasaki A, Hasegawa T, Watanabe M, Dalla-Bona DA, Yamano E, van Eijden TMGJ, Tanne K. Fibroblast Growth Factor-2 Augments Recombinant Human Bone Morphogenetic Protein-2-Induced Osteoinductive Activity. Ann Biomed Eng 2006; 34:717-25. [PMID: 16568346 DOI: 10.1007/s10439-006-9092-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Accepted: 02/16/2006] [Indexed: 10/24/2022]
Abstract
The osteoinductive activity induced by recombinant human BMP-2 (rhBMP-2) blunts proportionately as the recipient ages. In order to compensate for this bluntness administration of fibroblast growth factor-2 (FGF-2) has been considered. The aim of this study was to determine whether FGF-2 administration augments osteoinductive activity caused by rhBMP-2 and to evaluate the effect of aging on bone formation induced by coadministration of rhBMP-2 and FGF-2. Sixty-four Wistar strain male rats of 8-week-old (prepubertal) and 16-week-old (postpubertal) received bone defects bilaterally in the parietal bone and the defects were filled by a polylactic acid polyglycolic acid copolymer/gelatin sponge (PGS) impregnated with rhBMP-2 plus 0 ng, 25 ng, and 250 ng FGF-2 (n=10 in each). At 2 weeks after grafting, the new bone volume seemed to be larger in the rhBMP-2+FGF-2 groups than in the rhBMP-2 alone group. At 4 weeks, the new bone formation was linked to the adjacent original bone. In the prepubertal rats, all newly formed bone was similarly calcified. In the postpubertal rats, only the rhBMP-2+25 ng FGF-2 group showed this higher degree of calcification. At 2 weeks, alkaline phosphatase (ALP) activity in the rhBMP-2+25 ng FGF-2 group was significantly (p<0.05) larger than that in the rhBMP-2 group in both prepubertal and postpubertal rats. This result shows that low-dose administration of FGF-2 enhanced the degree of calcification and ALP activity in the rhBMP-2 grafting site especially in the postpubertal rats. Therefore, FGF-2 would be a candidate to compensate for the reduction of osteoinductive activity of rhBMP-2 with aging.
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Affiliation(s)
- Eiji Tanaka
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
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Degat MC, Ferreira E, Logeart-Avramoglou D. Utilisation de facteurs de croissance pour la réparation osseuse. ACTA ACUST UNITED AC 2005; 53:131-41. [PMID: 15781371 DOI: 10.1016/j.patbio.2004.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Accepted: 03/04/2004] [Indexed: 11/17/2022]
Abstract
Osteoformation is induced by numerous growth factors that play an important role in bone repair such as fracture healing. They may serve as therapeutic agent in the treatment of squeletal injuries in the orthopeadic and maxillo-facial fields. Among these proteins, Bone Morphogenetic Proteins (BMP) are the only known osteoinductive growth factors. Unfortunately, they are highly susceptible to proteolysis in vivo and require a suitable delivery system to potentiate their biological activity in a local, controlled and durable manner. In this aim, three options are under investigations: (i) osteoinductive materials made of appropriate carrier to release the protein in situ, (ii) in vivo gene therapy in which the gene is directly transfected in cells of the patient or (iii) ex vivo gene therapy in which cells are harvested from the patient, transfected with DNA in culture and then implanted in the defect. These different kinds of BMP delivery will be discussed.
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Affiliation(s)
- M-C Degat
- Laboratoire de recherches orthopédiques, CNRS UMR 7052, UFR Lariboisière-Saint-Louis, 10, avenue de Verdun, 75010 Paris, France
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Suga K, Saitoh M, Kokubo S, Nozaki K, Fukushima S, Yasuda S, Sasamata M, Miyata K. Synergism between interleukin-11 and bone morphogenetic protein-2 in the healing of segmental bone defects in a rabbit model. J Interferon Cytokine Res 2005; 24:343-9. [PMID: 15212708 DOI: 10.1089/107999004323142204] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recombinant human interleukin-11 (rHuIL-11) and recombinant human bone morphogenetic protein-2 (rHuBMP-2) have been shown to act synergistically in the induction of osteoblast differentiation. To determine whether these two proteins can be used clinically in fracture healing and reconstructive surgery, we investigated whether rHuIL-11 and rHuBMP-2 act synergistically to heal segmental bone defects in a rabbit model. A 1.5-cm segmental defect was created in the right ulnar diaphysis of 20 Japanese white rabbits. Polylactic-co-glycolic acid (PLGA)-coated gelatin sponges (PGS) permeated with rHuBMP-2 (n = 8), rHuIL-11 plus rHuBMP-2 (n = 8), or rHuIL-11 (n = 4) were implanted into the bone defects. Radiographs were scored by two independent observers for bone formation and union rates after 2, 3, 4, and 8 weeks. Bone formation was higher in rabbits implanted with rHuBMP-2 plus rHuIL-11 than in those implanted with rHuBMP-2 alone, reaching statistical significance after 4 weeks. At early time points, the union rate in rabbits implanted with rHuBMP-2 plus rHuIL-11 was higher than in rabbits implanted with rHuBMP-2. At 2, 4, and 8 weeks, new bone volume was significantly higher in rabbits administered rHuIL-11 plus rHuBMP-2 than in those given rHuBMP-2 alone. In contrast, mechanical testing after 8 weeks showed that bone strength in the two groups of rabbits was equivalent. These findings show that rHuIL-11 and rHuBMP-2 act synergistically to accelerate bone formation without affecting bone strength. Treatment with a combination of rHuIL-11 and rHuBMP-2 may thus be of great benefit in fracture healing and for patients undergoing reconstructive surgery.
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Affiliation(s)
- Kazutaka Suga
- Pharmacology Laboratories, Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co. Ltd., Tsukuba, Ibaraki, Japan.
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Kokubo S, Mochizuki M, Fukushima S, Ito T, Nozaki K, Iwai T, Takahashi K, Yokota S, Miyata K, Sasaki N. Long-term stability of bone tissues induced by an osteoinductive biomaterial, recombinant human bone morphogenetic protein-2 and a biodegradable carrier. Biomaterials 2004; 25:1795-803. [PMID: 14738843 DOI: 10.1016/j.biomaterials.2003.08.030] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The long-term stability of bone tissues induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) and poly[L-lactide-co-glycolide] copolymer-coated gelatin sponge (PGS) was examined. In 16 dogs, 2.5 cm unilateral bone defects were created in the left tibial diaphyses. Tibia was fixed with metal plate, and PGS impregnated with (0.4 mg/cm(3)) or without rhBMP-2 was implanted into 15 or one defects, respectively. The metal plates of rhBMP-2-treated limbs were removed 16 weeks after the implantation. The bilateral tibiae of five animals each of the rhBMP-2-treated group were harvested at 32, 52 or 104 weeks, and served for biomechanical testing and histology. Although the defect that received PGS alone resulted in nonunion at 16 weeks, all defects treated with rhBMP-2 achieved radiographic bony union by 8 weeks. Biomechanical properties of the regenerated bones restored to the levels of intact tibiae at 32 weeks, but torsional stiffness was significantly higher. No statistical significances were detected in all parameters between regenerated and intact tibiae at 104 weeks. No radiographic and histological findings suggesting enhanced resorption to the regenerated bones were observed. These results suggest the long-term stability of the bone tissues induced by rhBMP-2, and the usefulness of rhBMP-2-impregnated PGS as a biomaterial for long bone defect filling.
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Affiliation(s)
- Satoshi Kokubo
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka, Tsukuba, Ibaraki, Japan.
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Sotome S, Uemura T, Kikuchi M, Chen J, Itoh S, Tanaka J, Tateishi T, Shinomiya K. Synthesis and in vivo evaluation of a novel hydroxyapatite/collagen–alginate as a bone filler and a drug delivery carrier of bone morphogenetic protein. Materials Science and Engineering: C 2004; 24:341-7. [DOI: 10.1016/j.msec.2003.12.003] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Saito E, Saito A, Kawanami M. Favorable healing following space creation in rhBMP-2-induced periodontal regeneration of horizontal circumferential defects in dogs with experimental periodontitis. J Periodontol 2004; 74:1808-15. [PMID: 14974824 DOI: 10.1902/jop.2003.74.12.1808] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Recombinant human bone morphogenetic protein-2 (rhBMP-2) is believed to be capable of inducing periodontal regeneration. However, the risk of aberrant healing events, such as root resorption and ankylosis, has been reported. We hypothesized that implantation of BMP-containing carriers directly on the root planed surface may be the cause of unfavorable healing. The purpose of this study was to evaluate the influence of a 1 mm spacer membrane, which separated the rhBMP-2 in polymer-coated gelatin sponge (PGS) and the root surface, on periodontal regeneration of experimentally induced horizontal defects in dogs. METHODS Horizontal circumferential periodontal defects were surgically created, and experimental periodontitis was induced in 72 maxillary and mandibular premolars of four male beagle dogs. The recipient sites of each quadrant received: 1) rhBMP-2/PGS (B group) (rhBMP-2 at 1.0 mg/ml, total implant volume/ site approximately 7.2 microl) (n = 24); 2) rhBMP-2/PGS with a spacer membrane (PB group) (n = 24); and 3) physiological saline (PS)/PGS as a control (P group) (n = 24). One quadrant was left untreated. Dogs were sacrificed at 12 weeks post-surgery, and healing was evaluated histologically. RESULTS Both groups treated with rhBMP-2/PGS demonstrated enhanced new bone formation and connective tissue attachment with cementum regeneration when compared to the control group. Sites treated with rhBMP-2/PGS showed a greater degree of bone formation than sites treated with rhBMP-2/PGS and spacer membrane, although the latter sites showed no ankylosis. CONCLUSIONS Implantation of rhBMP-2/PGS enhances bone formation and connective tissue attachment in horizontal circumferential defects. In addition, the use of a spacer membrane reduces the degree of bone formation, but minimizes ankylosis.
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Affiliation(s)
- Emiko Saito
- Periodontology and Endodontology, Department of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan.
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Abstract
A bioactive and resorbable scaffold is necessary to exhibit the osteoinductive potency of recombinant human bone morphogenetic protein-2 (rhBMP-2). In a previous study, we found that synthetic octacalcium phosphate (OCP) enhances bone regeneration and is replaced by newly formed bone after it is resorbed. We hypothesized that OCP may be useful as an effective scaffold for rhBMP-2 to enhance bone regeneration. To test this hypothesis, the present study was designed to investigate whether an OCP/BMP composite implant could more effectively enhance bone regeneration. A critical-sized defect was made in a rat calvarium and 1. 15 mg of OCP combined with 10 microg of rhBMP-2 (OCP/BMP 10 microg), 2. 15 mg of OCP combined with 1 microg of rhBMP-2 (OCP/BMP 1 microg), or 3. OCP (OCP alone) was implanted into the defect and fixed at 4 or 8 weeks after implantation. The percentage of newly formed bone (n-Bone%) in the defect was determined by a histomorphometrical analysis. A statistical analysis showed that n-Bone% with OCP/BMP was significantly higher than that with OCP at both time points, whereas the difference in n-Bone% between OCP/BMP 10 microg and OCP/BMP 1 microg was not significant. The present results suggest that OCP can be used as an effective scaffold for rhBMP-2 and this OCP delivery system may be able to reduce the standard effective dose of rhBMP-2, which would be beneficial because low doses (<100 microg/g OCP) of rhBMP-2 enhance bone regeneration.
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Affiliation(s)
- S Kamakura
- Division of Clinical Cell Therapy, Department of Translational Research, Center for Translational and Advanced Animal Research, Tohoku University School of Medicine, 2-1 Seiryo-Machi, Aoba-Ku, Sendai 980-8574, Japan.
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Kokubo S, Fujimoto R, Yokota S, Fukushima S, Nozaki K, Takahashi K, Miyata K. Bone regeneration by recombinant human bone morphogenetic protein-2 and a novel biodegradable carrier in a rabbit ulnar defect model. Biomaterials 2003; 24:1643-51. [PMID: 12559824 DOI: 10.1016/s0142-9612(02)00551-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The effects of recombinant human bone morphogenetic protein (rhBMP)-2 and a novel carrier, PLGA-coated gelatin sponge (PGS), on bone defect repair was examined. A 1.5 cm unilateral segmental bone defect was created in the ulnar diaphysis of a Japanese white rabbit. In an initial study, defects were either treated with PGS impregnated with various concentrations of rhBMP-2 (0, 0.1, 0.4 and 1 mg/cm(3)) or left untreated. Defect healing was assessed by radiographic union rate, and biomechanical properties of regenerated bones were determined at 16 weeks postoperatively. In a second study, defects were implanted with PGS with or without rhBMP-2, and histologically observed at postoperative weeks 8 and 16. Radiographic union rate increased the dose-dependently at an early time point. All defects treated with rhBMP-2 (0.4 and 1 mg/cm(3)) were radiographically repaired. Mechanical properties of regenerated bones were restored in a dose-dependent manner. Neither ulnae left untreated nor implanted PGS alone showed radiographic union. Longitudinal alignment of lamellar structure was observed histologically at 16 weeks, indicating that remodeling of regenerated bone was complete. Implanted PGS was almost completely resorbed by 8 weeks, and no abnormalities were observed in the surrounding soft tissue. These results suggest that PGS is a promising carrier for rhBMP-2.
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Affiliation(s)
- Satoshi Kokubo
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka, Tsukuba, Ibaraki, Japan.
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Suga K, Saitoh M, Kokubo S, Fukushima S, Kaku S, Yasuda S, Miyata K. Interleukin-11 acts synergistically with bone morphogenetic protein-2 to accelerate bone formation in a rat ectopic model. J Interferon Cytokine Res 2003; 23:203-7. [PMID: 12856332 DOI: 10.1089/107999003765027401] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We previously demonstrated that recombinant human interleukin-11 (rHuIL-11) induced osteoblast differentiation of C3H10T1/2 progenitor cells and also acted synergistically with recombinant human bone morphogenetic protein-2 (rHuBMP-2) in performing the same function. In this study, we investigated the effect of rHuIL-11 and rHuBMP-2 on bone formation in a rat ectopic model. When placed in rats, implants consisting of polymer-coated gelatin sponges containing various concentrations of rHuBMP-2 showed a dose-dependent increase in calcium content. This was confirmed by radiographic analysis of the implants. Although implants containing rHuIL-11 alone did not accumulate calcium, implants containing a combination of rHuBMP-2 and rHuIL-11 had significantly higher calcium levels than those containing rHuBMP-2 alone. This increase was rHuIL-11 dose dependent. The synergistic effect of 20 micrograms rHuIL-11 and 6 micrograms rHuBMP-2 on bone formation was estimated to be 1 week in advance of that of 6 micrograms rHuBMP-2 alone. Histologic examination revealed that the combination of rHuIL-11 and rHuBMP-2 caused spindle cells to accumulate around implants and induced cell infiltration into implants. Bone formation occurred faster in implants with the combination of rHuIL-11 and rHuBMP-2 compared with rHuBMP-2 alone. These results suggest that rHuIL-11 acts synergistically with rHuBMP-2 to more rapidly stimulate bone formation compared with rHuBMP-2 alone. This novel combined therapy may be of great clinical benefit in bone healing.
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Affiliation(s)
- Kazutaka Suga
- Pharmacology Laboratories, Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., Tsukuba, Ibaraki, Japan.
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Yokota S, Uchida T, Kokubo S, Aoyama K, Fukushima S, Nozaki K, Takahashi T, Fujimoto R, Sonohara R, Yoshida M, Higuchi S, Yokohama S, Sonobe T. Release of recombinant human bone morphogenetic protein 2 from a newly developed carrier. Int J Pharm 2003; 251:57-66. [PMID: 12527175 DOI: 10.1016/s0378-5173(02)00581-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
After implantation of a polymer-coated gelatin sponge (PGS) containing either 0.4 or 1.0 mg of 125I-rhBMP-2 for each 1 cm(3) of PGS into the right ulnar of rabbits, changes in the level of radioactivity at the implant site and in the blood were measured for 21 days after implantation, and the cumulative excretion ratio of radioactivity in the urine and feces was calculated. For both doses, radioactivity at the implant site was eliminated biphasically. The concentration of trichloroacetic acid (TCA)-precipitable radioactivity in the blood reached a maximum 6 h after implantation, at which time it was equivalent to 1.41% of the administered dose (0.4 mg/cm(3)). The remaining radioactivity was eliminated rapidly thereafter, falling below the detection limit within 48 h. The t(1/2alpha) was about 0.1 days, the t(1/2beta) was about 3 days, and the mean resident time (MRT) value was about 4 days. By 17 days after implantation, 88.1% of the administered radioactivity had been excreted in the urine, and 1.7% had been excreted in the feces. TCA precipitation test results indicated that most of the radioactivity excreted in urine was a low-molecular weight decomposition product. At 21 days after implantation, the radioactivity of the PGS implant site had declined to 0.5% of the administered amount. Autoradiographs of the implant site taken 28 days after implantation revealed that, at both doses, the residual radioactivity was confined to the area of the implanted PGS. These results indicate that PGS retains an appropriate amount of recombinant human bone morphogenetic protein 2 (rhBMP-2) at the orthotopically implanted site for at least 21 days enough to induce bone regeneration. Thus, PGS shows great clinical potential as a carrier for rhBMP-2.
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Affiliation(s)
- S Yokota
- Institute for Drug Development and Research, Yamanouchi Pharmaceutical Co, Ltd, 180 Ozumi, Yaizu-shi, Shizuoka 425-0072, Japan.
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