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Kim YS, Gokcekaya O, Matsugaki A, Nakano T. Effect of Laser Scan Speed on Defects and Texture Development of Pure Chromium Metal Fabricated via Powder Bed Fusion-Laser Beam. Materials (Basel) 2024; 17:2097. [PMID: 38730906 PMCID: PMC11084875 DOI: 10.3390/ma17092097] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/28/2024] [Accepted: 04/28/2024] [Indexed: 05/13/2024]
Abstract
Chromium (Cr) metal has garnered significant attention in alloy systems owing to its exceptional properties, such as a high melting point, low density, and superior oxidation and corrosion resistance. However, its processing capabilities are hindered by its high ductile-brittle transition temperature (DBTT). Recently, powder bed fusion-laser beam for metals (PBF-LB/M) has emerged as a promising technique, offering the fabrication of net shapes and precise control over crystallographic texture. Nevertheless, research investigating the mechanism underlying crystallographic texture development in pure Cr via PBF-LB/M still needs to be conducted. This study explored the impact of scan speed on relative density and crystallographic texture. At the optimal scan speed, an increase in grain size attributed to epitaxial growth was observed, resulting in the formation of a <100> cubic texture. Consequently, a reduction in high-angle grain boundaries (HAGB) was achieved, suppressing defects such as cracks and enhancing relative density up to 98.1%. Furthermore, with increasing densification, Vickers hardness also exhibited a corresponding increase. These findings underscore the efficacy of PBF-LB/M for processing metals with high DBTT properties.
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Affiliation(s)
- Yong Seong Kim
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (Y.S.K.); (A.M.)
| | - Ozkan Gokcekaya
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (Y.S.K.); (A.M.)
- Anisotropic Design & Additive Manufacturing Research Center, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (Y.S.K.); (A.M.)
- Anisotropic Design & Additive Manufacturing Research Center, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (Y.S.K.); (A.M.)
- Anisotropic Design & Additive Manufacturing Research Center, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan
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Wang J, Ishimoto T, Matsuzaka T, Matsugaki A, Ozasa R, Matsumoto T, Hayashi M, Kim HS, Nakano T. Adaptive enhancement of apatite crystal orientation and Young's modulus under elevated load in rat ulnar cortical bone. Bone 2024; 181:117024. [PMID: 38266952 DOI: 10.1016/j.bone.2024.117024] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/02/2024] [Accepted: 01/19/2024] [Indexed: 01/26/2024]
Abstract
Functional adaptation refers to the active modification of bone structure according to the mechanical loads applied daily to maintain its mechanical integrity and adapt to the environment. Functional adaptation relates to bone mass, bone mineral density (BMD), and bone morphology (e.g., trabecular bone architecture). In this study, we discovered for the first time that another form of bone functional adaptation of a cortical bone involves a change in bone quality determined by the preferential orientation of apatite nano-crystallite, a key component of the bone. An in vivo rat ulnar axial loading model was adopted, to which a 3-15 N compressive load was applied, resulting in approximately 440-3200 μɛ of compression in the bone surface. In the loaded ulnae, the degree of preferential apatite c-axis orientation along the ulnar long axis increased in a dose-dependent manner up to 13 N, whereas the increase in BMD was not dose-dependent. The Young's modulus along the same direction was enhanced as a function of the degree of apatite orientation. This finding indicates that bone has a mechanism that modifies the directionality (anisotropy) of its microstructure, strengthening itself specifically in the loaded direction. BMD, a scalar quantity, does not allow for load-direction-specific strengthening. Functional adaptation through changes in apatite orientation is an excellent strategy for bones to efficiently change their strength in response to external loading, which is mostly anisotropic.
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Affiliation(s)
- Jun Wang
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Division of Material Science and Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China.
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Aluminium Research Center, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan.
| | - Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Takuya Matsumoto
- Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
| | - Mikako Hayashi
- Department of Restorative Dentistry and Endodontology, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Hyoung Seop Kim
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea.
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Watanabe R, Matsugaki A, Gokcekaya O, Ozasa R, Matsumoto T, Takahashi H, Yasui H, Nakano T. Host bone microstructure for enhanced resistance to bacterial infections. Biomater Adv 2023; 154:213633. [PMID: 37775399 DOI: 10.1016/j.bioadv.2023.213633] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 09/08/2023] [Accepted: 09/18/2023] [Indexed: 10/01/2023]
Abstract
Postoperative bacterial infection is a serious complication of orthopedic surgery. Not only infections that develop in the first few weeks after surgery but also late infections that develop years after surgery are serious problems. However, the relationship between host bone and infection activation has not yet been explored. Here, we report a novel association between host bone collagen/apatite microstructure and bacterial infection. The bone-mimetic-oriented micro-organized matrix structure was obtained by prolonged controlled cell alignment using a grooved-structured biomedical titanium alloy. Surprisingly, we have discovered that highly aligned osteoblasts have a potent inhibitory effect on Escherichia coli adhesion. Additionally, the oriented collagen/apatite micro-organization of the bone matrix showed excellent antibacterial resistance against Escherichia coli. The proposed mechanism for realizing the antimicrobial activity of the micro-organized bone matrix is by the controlled secretion of the antimicrobial peptides, including β-defensin 2 and β-defensin 3, from the highly aligned osteoblasts. Our findings contribute to the development of anti-infective strategies for orthopedic surgeries. The recovery of the intrinsically ordered bone matrix organization provides superior antibacterial resistance after surgery.
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Affiliation(s)
- Ryota Watanabe
- Teijin Nakashima Medical Co. Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan; Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan.
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan.
| | - Ozkan Gokcekaya
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan.
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan.
| | - Takuya Matsumoto
- Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
| | - Hiroyuki Takahashi
- Teijin Nakashima Medical Co. Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan.
| | - Hidekazu Yasui
- Teijin Nakashima Medical Co. Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan.
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan.
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Tanaka K, Ohara S, Matsuzaka T, Matsugaki A, Ishimoto T, Ozasa R, Kuroda Y, Matsuo K, Nakano T. Quantitative Threshold Determination of Auditory Brainstem Responses in Mouse Models. Int J Mol Sci 2023; 24:11393. [PMID: 37511152 PMCID: PMC10380451 DOI: 10.3390/ijms241411393] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
The auditory brainstem response (ABR) is a scalp recording of potentials produced by sound stimulation, and is commonly used as an indicator of auditory function. However, the ABR threshold, which is the lowest audible sound pressure, cannot be objectively determined since it is determined visually using a measurer, and this has been a problem for several decades. Although various algorithms have been developed to objectively determine ABR thresholds, they remain lacking in terms of accuracy, efficiency, and convenience. Accordingly, we proposed an improved algorithm based on the mutual covariance at adjacent sound pressure levels. An ideal ABR waveform with clearly defined waves I-V was created; moreover, using this waveform as a standard template, the experimentally obtained ABR waveform was inspected for disturbances based on mutual covariance. The ABR testing was repeated if the value was below the established cross-covariance reference value. Our proposed method allowed more efficient objective determination of ABR thresholds and a smaller burden on experimental animals.
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Affiliation(s)
- Kenji Tanaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Shuma Ohara
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Yukiko Kuroda
- Laboratory of Cell and Tissue Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Koichi Matsuo
- Laboratory of Cell and Tissue Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
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Matsugaki A, Ito M, Kobayashi Y, Matsuzaka T, Ozasa R, Ishimoto T, Takahashi H, Watanabe R, Inoue T, Yokota K, Nakashima Y, Kaito T, Okada S, Hanawa T, Matsuyama Y, Matsumoto M, Taneichi H, Nakano T. Innovative design of bone quality-targeted intervertebral spacer: accelerated functional fusion guiding oriented collagen and apatite microstructure without autologous bone graft. Spine J 2023; 23:609-620. [PMID: 36539040 DOI: 10.1016/j.spinee.2022.12.011] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 11/28/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022]
Abstract
BACKGROUND CONTEXT Although autologous bone grafting is widely considered as an ideal source for interbody fusion, it still carries a risk of nonunion. The influence of the intervertebral device should not be overlooked. Requirements for artificial spinal devices are to join the vertebrae together and recover the original function of the spine rapidly. Ordered mineralization of apatite crystals on collagen accelerates bone functionalization during the healing process. Particularly, the stable spinal function requires the ingrowth of an ordered collagen and apatite matrix which mimics the intact intervertebral microstructure. This collagen and apatite ordering is imperative for functional bone regeneration, which has not been achieved using classical autologous grafting. PURPOSE We developed an intervertebral body device to achieve high stability between the host bone and synthesized bone by controlling the ordered collagen and apatite microstructure. STUDY DESIGN This was an in vivo animal study. METHODS Intervertebral spacers with a through-pore grooved surface structure, referred to as a honeycomb tree structure, were produced using metal 3D printing. These spacers were implanted into normal sheep at the L2-L3 or L4-L5 disc levels. As a control group, grafting autologous bone was embedded. The mechanical integrity of the spacer/bone interface was evaluated through push-out tests. RESULTS The spacer with honeycomb tree structure induced anisotropic trabecular bone growth with textured collagen and apatite orientation in the through-pore and groove directions. The push-out load of the spacer was significantly higher than that of the conventional autologous graft spacer. Moreover, the load was significantly correlated with the anisotropic texture of the newly formed bone matrix. CONCLUSIONS The developed intervertebral spacer guided the regenerated bone matrix orientation of collagen and apatite, resulting in greater strength at the spacer/host bone interface than that obtained using a conventional gold-standard autologous bone graft. CLINICAL SIGNIFICANCE Our results provide a foundation for designing future spacers for interbody fusion in human.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Manabu Ito
- Department of Spine and Spinal Cord Disorders, National Hospital Organization, Hokkaido Medical Center,5-7-1-1, Yamanote, Nishi-ku, Sapporo, Hokkaido, 063-0005, Japan
| | - Yoshiya Kobayashi
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Hiroyuki Takahashi
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Ryota Watanabe
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Takayuki Inoue
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Katsuhiko Yokota
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Yoshio Nakashima
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Takashi Kaito
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Seiji Okada
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Takao Hanawa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan
| | - Yukihiro Matsuyama
- Department of Orthopaedic Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
| | - Morio Matsumoto
- Department of Orthopaedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hiroshi Taneichi
- Department of Orthopaedic Surgery, Dokkyo Medical University School of Medicine, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan.
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Watanabe R, Takahashi H, Matsugaki A, Uemukai T, Kogai Y, Imagama T, Yukata K, Nakano T, Sakai T. Novel nano-hydroxyapatite coating of additively manufactured three-dimensional porous implants improves bone ingrowth and initial fixation. J Biomed Mater Res B Appl Biomater 2023; 111:453-462. [PMID: 36169186 PMCID: PMC10087424 DOI: 10.1002/jbm.b.35165] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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: 05/09/2022] [Revised: 09/04/2022] [Accepted: 09/11/2022] [Indexed: 12/15/2022]
Abstract
Electron beam melting (EBM) has been used to fabricate three-dimensional (3D) porous Ti-6Al-4V surfaces for acetabular cups in total hip arthroplasty. However, there are radiographic concerns regarding poor implant fixation and bone ingrowth around electron beam melted (EBMed) 3D porous cups. We hypothesize that nano-hydroxyapatite (nHA) coating can promote bone ingrowth and thus decrease the occurrence of radiolucent lines around EBMed 3D porous cups. This study aimed to investigate the effect of a novel nHA coating on the biological performance of EBMed 3D porous implants in a beagle transcortical model. Low-porosity (control) and high-porosity 3D porous Ti-6Al-4V implants were manufactured using EBM. Half of the high-porosity implants were coated with nHA without clogging the 3D pores. Implants were inserted into the femoral diaphysis of the beagles. The beagles were euthanized at 4, 8, and 12 weeks postoperatively, and push-out testing was performed. Bone ingrowth was evaluated by histological analysis. Although the increase in porosity alone had no effect on biological behavior, the addition of nHA to high-porosity 3D implants significantly improved early bone fixation and bone ingrowth into the deep region of porous structures compared to low-porosity implants. This is the first report of a novel nHA coating that improved bone ingrowth into the deeper regions of 3D porous implants, which can prevent the occurrence of radiolucent lines around EBMed 3D porous cups.
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Affiliation(s)
- Ryota Watanabe
- R&D Center, Teijin Nakashima Medical Co., Ltd., Okayama, Okayama, Japan.,Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | | | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Toru Uemukai
- R&D Center, SofSera Co. Ltd., Ibaraki, Osaka, Japan
| | | | - Takashi Imagama
- Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Kiminori Yukata
- Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Takashi Sakai
- Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
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Ishimoto T, Kobayashi Y, Takahata M, Ito M, Matsugaki A, Takahashi H, Watanabe R, Inoue T, Matsuzaka T, Ozasa R, Hanawa T, Yokota K, Nakashima Y, Nakano T. Outstanding in vivo mechanical integrity of additively manufactured spinal cages with a novel "honeycomb tree structure" design via guiding bone matrix orientation. Spine J 2022; 22:1742-1757. [PMID: 35675865 DOI: 10.1016/j.spinee.2022.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 05/31/2022] [Accepted: 05/31/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Therapeutic devices for spinal disorders, such as spinal fusion cages, must be able to facilitate the maintenance and rapid recovery of spinal function. Therefore, it would be advantageous that future spinal fusion cages facilitate rapid recovery of spinal function without secondary surgery to harvest autologous bone. PURPOSE This study investigated a novel spinal cage configuration that achieves in vivo mechanical integrity as a devise/bone complex by inducing bone that mimicked the sound trabecular bone, hierarchically and anisotropically structured trabeculae strengthened with a preferentially oriented extracellular matrix. STUDY DESIGN/SETTINGS In vivo animal study. METHODS A cage possessing an anisotropic through-pore with a grooved substrate, that we termed "honeycomb tree structure," was designed for guiding bone matrix orientation; it was manufactured using a laser beam powder bed fusion method through an additive manufacturing processes. The newly designed cages were implanted into sheep vertebral bodies for 8 and 16 weeks. An autologous bone was not installed in the newly designed cage. A pull-out test was performed to evaluate the mechanical integrity of the cage/bone interface. Additionally, the preferential orientation of bone matrix consisting of collagen and apatite was determined. RESULTS The cage/host bone interface strength assessed by the maximum pull-out load for the novel cage without an autologous bone graft (3360±411 N) was significantly higher than that for the conventional cage using autologous bone (903±188 N) after only 8 weeks post-implantation. CONCLUSIONS These results highlight the potential of this novel cage to achieve functional fusion between the cage and host bone. Our study provides insight into the design of highly functional spinal devices based on the anisotropic nature of bone. CLINICAL SIGNIFICANCE The sheep spine is similar to the human spine in its stress condition and trabecular bone architecture and is widely recognized as a useful model for the human spine. The present design may be useful as a new spinal device for humans.
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Affiliation(s)
- Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Yoshiya Kobayashi
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Masahiko Takahata
- Department of Orthopedic Surgery, Graduate School of Medicine, Hokkaido University, North-15, West-7, Kita-ku, Sapporo, Hokkaido, 060-8638, Japan
| | - Manabu Ito
- Department of Spine and Spinal Cord Disorders, National Hospital Organization, Hokkaido Medical Center, 5-7-1-1, Yamanote, Nishi-ku, Sapporo, Hokkaido, 063-0005, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Hiroyuki Takahashi
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Ryota Watanabe
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Takayuki Inoue
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Takao Hanawa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan
| | - Katsuhiko Yokota
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Yoshio Nakashima
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama, 709-0625, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan; Anisotropic Design and Additive Manufacturing Research Center, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan.
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Watanabe R, Matsugaki A, Ishimoto T, Ozasa R, Matsumoto T, Nakano T. A Novel Ex Vivo Bone Culture Model for Regulation of Collagen/Apatite Preferential Orientation by Mechanical Loading. Int J Mol Sci 2022; 23:ijms23137423. [PMID: 35806427 PMCID: PMC9267238 DOI: 10.3390/ijms23137423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/29/2022] [Accepted: 07/01/2022] [Indexed: 11/16/2022] Open
Abstract
The anisotropic microstructure of bone, composed of collagen fibers and biological apatite crystallites, is an important determinant of its mechanical properties. Recent studies have revealed that the preferential orientation of collagen/apatite composites is closely related to the direction and magnitude of in vivo principal stress. However, the mechanism of alteration in the collagen/apatite microstructure to adapt to the mechanical environment remains unclear. In this study, we established a novel ex vivo bone culture system using embryonic mouse femurs, which enabled artificial control of the mechanical environment. The mineralized femur length significantly increased following cultivation; uniaxial mechanical loading promoted chondrocyte hypertrophy in the growth plates of embryonic mouse femurs. Compressive mechanical loading using the ex vivo bone culture system induced a higher anisotropic microstructure than that observed in the unloaded femur. Osteocytes in the anisotropic bone microstructure were elongated and aligned along the long axis of the femur, which corresponded to the principal loading direction. The ex vivo uniaxial mechanical loading successfully induced the formation of an oriented collagen/apatite microstructure via osteocyte mechano-sensation in a manner quite similar to the in vivo environment.
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Affiliation(s)
- Ryota Watanabe
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan; (R.W.); (A.M.); (T.I.); (R.O.)
- Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan; (R.W.); (A.M.); (T.I.); (R.O.)
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan; (R.W.); (A.M.); (T.I.); (R.O.)
| | - Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan; (R.W.); (A.M.); (T.I.); (R.O.)
| | - Takuya Matsumoto
- Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan;
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan; (R.W.); (A.M.); (T.I.); (R.O.)
- Correspondence: ; Tel.: +81-6-6879-7505
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9
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Ozasa R, Saito M, Ishimoto T, Matsugaki A, Matsumoto Y, Nakano T. Combination treatment with ibandronate and eldecalcitol prevents osteoporotic bone loss and deterioration of bone quality characterized by nano-arrangement of the collagen/apatite in an ovariectomized aged rat model. Bone 2022; 157:116309. [PMID: 34998980 DOI: 10.1016/j.bone.2021.116309] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 12/13/2022]
Abstract
Combination therapy with bisphosphonates and vitamin D3 analogs has been frequently used for the treatment of osteoporosis. However, its effects on bone anisotropies, such as orientations of collagen and apatite at the nanometer-scale, which is a promising bone quality index, and its trabecular architecture at the micrometer scale, are not well understood despite its important mechanical properties and its role in fracture risk. In the present study, we analyzed the effects of ibandronate (IBN), eldecalcitol (ELD), and their combination on the collagen/apatite orientation and trabecular architectural anisotropy using an estrogen-deficiency-induced osteoporotic rat model. Estrogen deficiency caused by ovariectomy (OVX) excessively increased the degree of collagen/apatite orientation or trabecular architectural anisotropy along the craniocaudal axis in the lumbar vertebra compared to that of the sham-operated group. The craniocaudal axis corresponds to the direction of principal stress in the spine. The excessive material anisotropy in the craniocaudal axis contributed to the enhanced Young's modulus, which may compensate for the reduced mechanical resistance by bone loss to some extent. The solo administration of IBN and ELD prevented the reduction of bone fraction (BV/TV) determined by μ-CT, and combination therapy showed the highest efficacy in BV/TV gain. Furthermore, the solo administration and combination treatment significantly decreased the degree of collagen/apatite orientation to the sham level. Based on the results of bone mass and collagen/apatite orientation, combination treatment is an effective strategy. This is the first report to demonstrate the efficacy of IBN, ELD, and combination treatment with IBN and ELD relative to the bone micro-architectural anisotropy characterized by collagen/apatite orientation.
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Affiliation(s)
- Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Mitsuru Saito
- Department of Orthopaedic Surgery, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan.
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yoshihiro Matsumoto
- Product Research Department, Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd., 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan.
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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10
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Ozasa R, Matsugaki A, Ishimoto T, Kamura S, Yoshida H, Magi M, Matsumoto Y, Sakuraba K, Fujimura K, Miyahara H, Nakano T. Bone fragility via degradation of bone quality featured by collagen/apatite micro-arrangement in human rheumatic arthritis. Bone 2022; 155:116261. [PMID: 34826630 DOI: 10.1016/j.bone.2021.116261] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/20/2022]
Abstract
Although increased bone fragility is a well-recognized consequence in patients with rheumatoid arthritis (RA), the essential cause of degenerate bone strength remains unknown. This study aimed to determine factors contributing to bone dysfunction in RA by focusing on the bone matrix micro-arrangement, based on the preferential orientation of collagen and the related apatite c-axis as a bone quality index. The classical understanding of RA is limited to its severe pathological conditions associated with inflammation-induced bone loss. This study examined periarticular proximal tibiae from RA patients as compared with osteoarthritis (OA) patients as controls. Bone tissue material strength was disrupted in the RA group compared with the control. Collagen/apatite micro-arrangement and vBMD were significantly lower in the RA group, and the rate of decrease in apatite c-axis orientation (-45%) was larger than that in vBMD (-22%). Multiple regression analysis showed that the degree of apatite c-axis orientation (β = 0.52, p = 1.9 × 10-2) significantly contributed to RA-induced bone material impairment as well as vBMD (β = 0.46, p = 3.8 × 10-2). To the best of our knowledge, this is the first report to demonstrate that RA reduces bone material strength by deteriorating the micro-arrangement of collagen/apatite bone matrix, leading to decreased fracture resistance. Our findings represent the significance of bone quality-based analysis for precise evaluation and subsequent therapy of the integrity and soundness of the bone in patients with RA.
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Affiliation(s)
- Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Satoshi Kamura
- Department of Orthopaedic Surgery, National Hospital Organization, Kyushu Medical Center, 1-8-1 Jigyouhama chuo-ku, Fukuoka, Fukuoka 811-1395, Japan
| | - Hiroto Yoshida
- Product Research Department, Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd., 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan
| | - Mayu Magi
- Product Research Department, Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd., 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan
| | - Yoshihiro Matsumoto
- Product Research Department, Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd., 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan
| | - Koji Sakuraba
- Department of Orthopaedic Surgery, National Hospital Organization, Kyushu Medical Center, 1-8-1 Jigyouhama chuo-ku, Fukuoka, Fukuoka 811-1395, Japan
| | - Kenjiro Fujimura
- Department of Orthopaedic Surgery, National Hospital Organization, Kyushu Medical Center, 1-8-1 Jigyouhama chuo-ku, Fukuoka, Fukuoka 811-1395, Japan
| | - Hisaaki Miyahara
- Department of Orthopaedic Surgery, National Hospital Organization, Kyushu Medical Center, 1-8-1 Jigyouhama chuo-ku, Fukuoka, Fukuoka 811-1395, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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11
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Matsuzaka T, Matsugaki A, Nakano T. Control of osteoblast arrangement by osteocyte mechanoresponse through prostaglandin E2 signaling under oscillatory fluid flow stimuli. Biomaterials 2021; 279:121203. [PMID: 34717197 DOI: 10.1016/j.biomaterials.2021.121203] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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: 11/10/2020] [Revised: 10/07/2021] [Accepted: 10/20/2021] [Indexed: 01/04/2023]
Abstract
Anisotropic collagen/apatite microstructure is a prominent determinant of bone tissue functionalization; in particular, bone matrix modulates its anisotropic microstructure depending on the surrounding mechanical condition. Although mechanotransduction in bones is governed by osteocyte function, the precise mechanisms linking mechanical stimuli and anisotropic formation of collagen/apatite microstructure are poorly understood. Here we developed a novel anisotropic mechano-coculture system which enables the understanding of the biological mechanisms regulating the oriented bone matrix formation, which is constructed by aligned osteoblasts. The developed model provides bone-mimetic coculture platform that enables simultaneous control of mechanical condition and osteoblast-osteocyte communication with an anisotropic culture scaffold. The engineered coculture device helps in understanding the relationship between osteocyte mechanoresponses and osteoblast arrangement, which is a significant contributor to anisotropic organization of bone tissue. Our study showed that osteocyte responses to oscillatory flow stimuli regulated osteoblast arrangement through soluble molecular interactions. Importantly, we found that prostaglandin E2 is a novel determinant for oriented collagen/apatite organization of bone matrix, through controlling osteoblast arrangement.
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Affiliation(s)
- Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan.
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12
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Ishimoto T, Kawahara K, Matsugaki A, Kamioka H, Nakano T. Quantitative Evaluation of Osteocyte Morphology and Bone Anisotropic Extracellular Matrix in Rat Femur. Calcif Tissue Int 2021; 109:434-444. [PMID: 34009396 PMCID: PMC8429393 DOI: 10.1007/s00223-021-00852-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/16/2021] [Indexed: 12/22/2022]
Abstract
Osteocytes are believed to play a crucial role in mechanosensation and mechanotransduction which are important for maintenance of mechanical integrity of bone. Recent investigations have revealed that the preferential orientation of bone extracellular matrix (ECM) mainly composed of collagen fibers and apatite crystallites is one of the important determinants of bone mechanical integrity. However, the relationship between osteocytes and ECM orientation remains unclear. In this study, the association between ECM orientation and anisotropy in the osteocyte lacuno-canalicular system, which is thought to be optimized along with the mechanical stimuli, was investigated using male rat femur. The degree of ECM orientation along the femur longitudinal axis was significantly and positively correlated with the anisotropic features of the osteocyte lacunae and canaliculi. At the femur middiaphysis, there are the osteocytes with lacunae that highly aligned along the bone long axis (principal stress direction) and canaliculi that preferentially extended perpendicular to the bone long axis, and the highest degree of apatite c-axis orientation along the bone long axis was shown. Based on these data, we propose a model in which osteocytes can change their lacuno-canalicular architecture depending on the mechanical environment so that they can become more susceptible to mechanical stimuli via fluid flow in the canalicular channel.
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Affiliation(s)
- Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Keita Kawahara
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Hiroshi Kamioka
- Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8558, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-Oka, Suita, Osaka, 565-0871, Japan.
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13
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Matsugaki A, Kimura Y, Watanabe R, Nakamura F, Takehana R, Nakano T. Impaired Alignment of Bone Matrix Microstructure Associated with Disorganized Osteoblast Arrangement in Malignant Melanoma Metastasis. Biomolecules 2021; 11:131. [PMID: 33498283 PMCID: PMC7909255 DOI: 10.3390/biom11020131] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 01/04/2023] Open
Abstract
Malignant melanoma favors spreading to bone, resulting in a weakened bone with a high fracture risk. Here, we revealed the disorganized alignment of apatite crystals in the bone matrix associated with the homing of cancer cells by developing an artificially controlled ex vivo melanoma bone metastasis model. The ex vivo metastasis model reflects the progressive melanoma cell activation in vivo, resulting in decreased bone mineral density and expression of MMP1-positive cells. Moreover, less organized intercellular connections were observed in the neighboring osteoblasts in metastasized bone, indicating the abnormal and randomized organization of bone matrix secreted by disconnected osteoblasts. Our study revealed that the deteriorated microstructure associated with disorganized osteoblast arrangement was a determinant of malignant melanoma-related bone dysfunction.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
| | - Yumi Kimura
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
| | - Ryota Watanabe
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
- Teijin Nakashima Medical Co. Ltd., 688-1, Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan
| | - Fumihito Nakamura
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
| | - Ryo Takehana
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (Y.K.); (R.W.); (F.N.); (R.T.)
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14
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Matsugaki A, Matsumoto S, Nakano T. A Novel Role of Interleukin-6 as a Regulatory Factor of Inflammation-Associated Deterioration in Osteoblast Arrangement. Int J Mol Sci 2020; 21:E6659. [PMID: 32932973 PMCID: PMC7555301 DOI: 10.3390/ijms21186659] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022] Open
Abstract
Inflammatory disorders are associated with bone destruction; that is, deterioration in bone cell activities are under the control of the innate immune system. Macrophages play a central role in innate immunity by switching their polarized phenotype. A disturbed immune system causes aberrance in the ordered bone matrix microarrangement, which is a dominant determinant of bone tissue functionalization. However, the precise relationship between the immune system and bone tissue organization is unknown. In this study, the controlled in vitro co-culture assay results showed that M1-polarized macrophages disrupted the osteoblast alignment, which directly modulate the oriented bone matrix organization, by secreting pro-inflammatory cytokines. Notably, interleukin-6 was found to be a key regulator of unidirectional osteoblast alignment. Our results demonstrated that inflammatory diseases triggered bone dysfunction by regulating the molecular interaction between the immune system and bone tissue organization. These findings may contribute to the development of therapeutic targets for inflammatory disorders, including rheumatoid arthritis.
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Affiliation(s)
| | | | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; (A.M.); (S.M.)
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15
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Matsugaki A, Matsuzaka T, Murakami A, Wang P, Nakano T. 3D Printing of Anisotropic Bone-Mimetic Structure with Controlled Fluid Flow Stimuli for Osteocytes: Flow Orientation Determines the Elongation of Dendrites. Int J Bioprint 2020; 6:293. [PMID: 33088998 PMCID: PMC7557340 DOI: 10.18063/ijb.v6i4.293] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [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: 06/03/2020] [Accepted: 06/25/2020] [Indexed: 02/07/2023] Open
Abstract
Although three-dimensional (3D) bioprinting techniques enable the construction of various living tissues and organs, the generation of bone-like oriented microstructures with anisotropic texture remains a challenge. Inside the mineralized bone matrix, osteocytes play mechanosensing roles in an ordered manner with a well-developed lacunar-canaliculi system. Therefore, control of cellular arrangement and dendritic processes is indispensable for construction of artificially controlled 3D bone-mimetic architecture. Herein, we propose an innovative methodology to induce controlled arrangement of osteocyte dendritic processes using the laminated layer method of oriented collagen sheets, combined with a custom-made fluid flow stimuli system. Osteocyte dendritic processes showed elongation depending on the competitive directional relationship between flow and substrate. To the best of our knowledge, this study is the first to report the successful construction of the anisotropic bone-mimetic microstructure and further demonstrate that the dendritic process formation in osteocytes can be controlled with selective fluid flow stimuli, specifically by regulating focal adhesion. Our results demonstrate how osteocytes adapt to mechanical stimuli by optimizing the anisotropic maturation of dendritic cell processes.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Tadaaki Matsuzaka
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Ami Murakami
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Pan Wang
- Singapore Institute of Manufacturing Technology, 73 Nanyang Drive, 637662, Singapore
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
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16
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Matsugaki A, Yamazaki D, Nakano T. Selective patterning of netrin-1 as a novel guiding cue for anisotropic dendrogenesis in osteocytes. Mater Sci Eng C Mater Biol Appl 2019; 108:110391. [PMID: 31923977 DOI: 10.1016/j.msec.2019.110391] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/02/2019] [Accepted: 10/31/2019] [Indexed: 11/17/2022]
Abstract
Although protein patterning approaches have found widespread applications in tuning surface characteristics of biomaterials, selective control of growth in cell body and dendrites utilizing such platforms remains difficult. The functional roles assumed by cell body and dendrites in a physiological milieu have extremely high specificity. In particular, osteocytes embedded inside the mineralized bone matrix are interconnected via dendritic cell processes characterized by an anisotropic arrangement of the lacunar-canalicular system, where the fluid-flow inside the canaliculi system regulates the mechanoresponsive functionalization of bone. Control of cellular networks connected by dendritic cell processes is, therefore, imperative for constructing artificially controlled bone-mimetic structures and as an extension, for gaining insights into the molecular mechanisms underlying dendrogenesis inside the mineralized bone matrix. Here, we report an innovative strategy to induce controlled elongation of cell body or dendritic process structures in selective directions by using the inkjet printing technique. Artificial runways employing netrin-1, inspired by neural architecture, were utilized to trigger controlled elongation in the osteocyte dendritic processes in desired directions. This is the first report, to the best of our knowledge, demonstrating that anisotropic dendrogenesis of osteocytes can be controlled with selective patterning of extracellular proteins, specifically via the axon guidance ligand netrin-1.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Daisuke Yamazaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan.
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17
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Nagase T, Iijima Y, Matsugaki A, Ameyama K, Nakano T. Design and fabrication of Ti-Zr-Hf-Cr-Mo and Ti-Zr-Hf-Co-Cr-Mo high-entropy alloys as metallic biomaterials. Mater Sci Eng C Mater Biol Appl 2019; 107:110322. [PMID: 31761171 DOI: 10.1016/j.msec.2019.110322] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/19/2019] [Accepted: 10/14/2019] [Indexed: 11/29/2022]
Abstract
Novel TiZrHfCr0.2Mo and TiZrHfCo0.07Cr0.07Mo high-entropy alloys for metallic biomaterials (bio-HEAs) were developed based on the combination of Ti-Nb-Ta-Zr-Mo alloy system and Co-Cr-Mo alloy system as commercially-used metallic biomaterials. Ti-Zr-Hf-Cr-Mo and Ti-Zr-Hf-Co-Cr-Mo bio-HEAs were designed using (a) a tree-like diagram for alloy development, (b) empirical alloy parameters for solid-solution-phase formation, and (c) thermodynamic calculations focused on solidification. The newly-developed bio-HEAs overcomes the limitation of classical metallic biomaterials by the improvement of (i) mechanical hardness and (ii) biocompatibility all together. The TiZrHfCr0.2Mo and TiZrHfCo0.07Cr0.07Mo bio-HEAs showed superior biocompatibility comparable to that of commercial-purity Ti. The superior biocompatibility, high mechanical hardness and low liquidus temperature for the material processing in TiZrHfCr0.2Mo and TiZrHfCo0.07Cr0.07Mo bio-HEAs compared with the Ti-Nb-Ta-Zr-Mo bio-HEAs gave the authenticity of the application of bio-HEAs for orthopedic implants with multiple functions.
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Affiliation(s)
- Takeshi Nagase
- Research Center for Ultra-High-Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan; Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yuuka Iijima
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Kei Ameyama
- Department of Mechanical Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga, 525-8577, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871, Japan.
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18
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Nakanishi Y, Matsugaki A, Kawahara K, Ninomiya T, Sawada H, Nakano T. Unique arrangement of bone matrix orthogonal to osteoblast alignment controlled by Tspan11-mediated focal adhesion assembly. Biomaterials 2019; 209:103-110. [PMID: 31030082 DOI: 10.1016/j.biomaterials.2019.04.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [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: 10/09/2018] [Revised: 04/10/2019] [Accepted: 04/11/2019] [Indexed: 12/20/2022]
Abstract
During tissue construction, cells coordinate extracellular matrix (ECM) assembly depending on the cellular arrangement. The traditional understanding of the relationship between the ECM and cells is limited to the orientation-matched interaction between them. Indeed, it is commonly accepted that the bone matrix (collagen/apatite) is formed along osteoblast orientation. Nonetheless, our recent findings are contrary to the above theory; osteoblasts on nanogrooves organize formation of the bone matrix perpendicular to cell orientation. However, the precise molecular mechanisms underlying the orthogonal organization of bone matrix are still unknown. Here, we show that mature fibrillar focal adhesions (FAs) facilitate the perpendicular arrangement between cells and bone matrix. The osteoblasts aligned along nanogrooves expressed highly mature fibrillar FAs mediated by integrin clustering. Microarray analysis revealed that Tspan11, a member of the transmembrane tetraspanin protein family, was upregulated in cells on the nanogrooved surface compared with that in cells on isotropic, flat, or rough surfaces. Tspan11 silencing significantly disrupted osteoblast alignment and further construction of aligned bone matrix orthogonal to cell orientation. Our results demonstrate that the unique bone matrix formation orthogonal to cell alignment is facilitated by FA maturation. To the best of our knowledge, this report is the first to show that FA assembly mediated by Tspan11 determines the direction of bone matrix organization.
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Affiliation(s)
- Yohei Nakanishi
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Kosuke Kawahara
- Canon Machinery Inc., Shiga 85 Minami Yamada-cho, Kusatsu, Shiga, 525-8511, Japan
| | - Takafumi Ninomiya
- Canon Machinery Inc., Shiga 85 Minami Yamada-cho, Kusatsu, Shiga, 525-8511, Japan
| | - Hiroshi Sawada
- Canon Machinery Inc., Shiga 85 Minami Yamada-cho, Kusatsu, Shiga, 525-8511, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan.
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Lee S, Matsugaki A, Kasuga T, Nakano T. Development of bifunctional oriented bioactive glass/poly(lactic acid) composite scaffolds to control osteoblast alignment and proliferation. J Biomed Mater Res A 2019; 107:1031-1041. [PMID: 30675975 PMCID: PMC6593822 DOI: 10.1002/jbm.a.36619] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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: 08/03/2018] [Revised: 10/12/2018] [Accepted: 11/06/2018] [Indexed: 01/27/2023]
Abstract
During the bone regeneration process, the anisotropic microstructure of bone tissue (bone quality) recovers much later than bone mass (bone quantity), resulting in severe mechanical dysfunction in the bone. Hence, restoration of bone microstructure in parallel with bone mass is necessary for ideal bone tissue regeneration; for this, development of advanced bifunctional biomaterials, which control both the quality and quantity in regenerated bone, is required. We developed novel oriented bioactive glass/poly(lactic acid) composite scaffolds by introducing an effective methodology for controlling cell alignment and proliferation, which play important roles for achieving bone anisotropy and bone mass, respectively. Our strategy is to manipulate the cell alignment and proliferation by the morphological control of the scaffolds in combination with controlled ion release from bioactive glasses. We quantitatively controlled the morphology of fibermats containing bioactive glasses by electrospinning, which successfully induced cell alignment along the fibermats. Also, the substitution of CaO in Bioglass®(45S5) with MgO and SrO improved osteoblast proliferation, indicating that dissolved Mg2+ and Sr2+ ions promoted cell adhesion and proliferation. Our results indicate that the fibermats developed in this work are candidates for the scaffolds to bone tissue regeneration that enable recovery of both bone quality and bone quantity. © 2019 The Authors. journal Of Biomedical Materials Research Part A Published By Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1031–1041, 2019.
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Affiliation(s)
- Sungho Lee
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Toshihiro Kasuga
- Division of Advanced Ceramics, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
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Matsugaki A, Harada T, Kimura Y, Sekita A, Nakano T. Dynamic Collision Behavior Between Osteoblasts and Tumor Cells Regulates the Disordered Arrangement of Collagen Fiber/Apatite Crystals in Metastasized Bone. Int J Mol Sci 2018; 19:ijms19113474. [PMID: 30400633 PMCID: PMC6274720 DOI: 10.3390/ijms19113474] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 10/25/2018] [Accepted: 11/02/2018] [Indexed: 01/09/2023] Open
Abstract
Bone metastasis is one of the most intractable bone diseases; it is accompanied with a severe mechanical dysfunction of bone tissue. We recently discovered that the disorganized collagen/apatite microstructure in cancer-bearing bone is a dominant determinant of the disruption of bone mechanical function; disordered osteoblast arrangement was found to be one of the principal determinants of the deteriorated collagen/apatite microstructure. However, the precise molecular mechanisms regulating the disordered osteoblast arrangement triggered by cancer invasion are not yet understood. Herein, we demonstrate a significant disorganization of bone tissue anisotropy in metastasized bone in our novel ex vivo metastasis model. Further, we propose a novel mechanism underlying the disorganization of a metastasized bone matrix: A dynamic collision behavior between tumor cells and osteoblasts disturbs the osteoblast arrangement along the collagen substrate.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 5650871, Japan.
| | - Tatsuki Harada
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 5650871, Japan.
| | - Yumi Kimura
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 5650871, Japan.
| | - Aiko Sekita
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 5650871, Japan.
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 5650871, Japan.
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Ozasa R, Matsugaki A, Isobe Y, Saku T, Yun HS, Nakano T. Construction of human induced pluripotent stem cell-derived oriented bone matrix microstructure by using in vitro engineered anisotropic culture model. J Biomed Mater Res A 2017; 106:360-369. [PMID: 28921822 PMCID: PMC5765486 DOI: 10.1002/jbm.a.36238] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [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: 07/04/2017] [Revised: 09/01/2017] [Accepted: 09/14/2017] [Indexed: 01/27/2023]
Abstract
Bone tissue has anisotropic microstructure based on collagen/biological apatite orientation, which plays essential roles in the mechanical and biological functions of bone. However, obtaining an appropriate anisotropic microstructure during the bone regeneration process remains a great challenging. A powerful strategy for the control of both differentiation and structural development of newly‐formed bone is required in bone tissue engineering, in order to realize functional bone tissue regeneration. In this study, we developed a novel anisotropic culture model by combining human induced pluripotent stem cells (hiPSCs) and artificially‐controlled oriented collagen scaffold. The oriented collagen scaffold allowed hiPSCs‐derived osteoblast alignment and further construction of anisotropic bone matrix which mimics the bone tissue microstructure. To the best of our knowledge, this is the first report showing the construction of bone mimetic anisotropic bone matrix microstructure from hiPSCs. Moreover, we demonstrated for the first time that the hiPSCs‐derived osteoblasts possess a high level of intact functionality to regulate cell alignment. © 2017 The Authors Journal of Biomedical Materials Research Part A Published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 360–369, 2018.
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Affiliation(s)
- Ryosuke Ozasa
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Yoshihiro Isobe
- Atree, Inc., 16-12-1 Hiroo, Shibuya-ku, Tokyo, 150-0012, Japan
| | - Taro Saku
- Atree, Inc., 16-12-1 Hiroo, Shibuya-ku, Tokyo, 150-0012, Japan
| | - Hui-Suk Yun
- Powder and Ceramics Division, Korea Institute of Materials Science, Changwon, Gyeongnam, 642-831, Korea
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
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Furuta M, Matsugaki A, Nakano T, Hirata I, Kato K, Oda T, Sato M, Okazaki M. Molecular level analyses of mechanical properties of PTFE sterilized by Co-60 γ-ray irradiation for clinical use. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2017.04.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Sekita A, Matsugaki A, Nakano T. Disruption of collagen/apatite alignment impairs bone mechanical function in osteoblastic metastasis induced by prostate cancer. Bone 2017; 97:83-93. [PMID: 28069516 DOI: 10.1016/j.bone.2017.01.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 01/05/2017] [Accepted: 01/05/2017] [Indexed: 01/22/2023]
Abstract
Prostate cancer (PCa) frequently metastasizes to the bone, generally inducing osteoblastic alterations that increase bone brittleness. Although there is growing interest in the management of the physical capability of patients with bone metastasis, the mechanism underlying the impairment of bone mechanical function remains unclear. The alignment of both collagen fibrils and biological apatite (BAp) c-axis, together with bone mineral density, is one of the strongest contributors to bone mechanical function. In this study, we analyzed the bone microstructure of the mouse femurs with and without PCa cell inoculation. Histological assessment revealed that the bone-forming pattern in the PCa-bearing bone was non-directional, resulting in a spongious structure, whereas that in the control bone was unidirectional and layer-by-layer, resulting in a compact lamellar structure. The degree of preferential alignment of collagen fibrils and BAp, which was evaluated by quantitative polarized microscopy and microbeam X-ray diffraction, respectively, were significantly lower in the PCa-bearing bone than in the control bone. Material parameters including Young's modulus and toughness, measured by the three-point bending test, were simultaneously decreased in the PCa-bearing bone. Specifically, there was a significant positive correlation between the degree of BAp c-axis orientation and Young's modulus. In conclusion, the impairment of mechanical function in the PCa-bearing bone is attributable to disruption of the anisotropic microstructure of bone in multiple phases. This is the first report demonstrating that cancer bone metastasis induces disruption of the collagen/BAp alignment in long bones, thereby impairing their mechanical function.
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Affiliation(s)
- Aiko Sekita
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
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Sekita A, Matsugaki A, Ishimoto T, Nakano T. Synchronous disruption of anisotropic arrangement of the osteocyte network and collagen/apatite in melanoma bone metastasis. J Struct Biol 2016; 197:260-270. [PMID: 27989794 DOI: 10.1016/j.jsb.2016.12.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [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: 10/02/2016] [Revised: 12/07/2016] [Accepted: 12/09/2016] [Indexed: 12/01/2022]
Abstract
Cancer metastasis to bones increases the risk of fragility fracture by altering bone metabolism and disrupting bone structure. Osteocytes, which organize a dense network that is closely linked with the circumambient matrix, play a key role in regulation of bone microstructure and material properties. The aim of this study was to elucidate the influence of cancer metastasis on the organization of the osteocyte network and collagen/biological apatite (BAp) microstructure in the context of osteocyte/matrix coupling. Using a mouse model intracardially injected with B16F10 melanoma cells or vehicle, the geometric and metabolic changes to osteocytes were analyzed by nano-computed tomography (nano-CT) and histology, and the alignment of collagen fibrils and BAp was analyzed by birefringence measurement and microbeam-X-ray diffraction, respectively. The material properties of bones were further analyzed with nanoindentation method. These experiments revealed that the osteocyte network was markedly disorganized in cancer-bearing bone tissues. The osteocytes showed a variety of residing states in the lacunae; some lacunae were osteolytic while some were replete with immature matrix, suggesting significant disruption in osteocyte/matrix coupling. Collagen/BAp microstructure was also disorganized in cancer-bearing bones as observed by significant decreases in the preferential alignment of both collagen fibrils and BAp; the latter was further shown to be significantly correlated with Young's modulus. The present study revealed that the disruption in the arrangement of the osteocyte network and collagen/BAp microstructure and the deterioration of mechanical function occurred synchronously during cancer bone metastasis.
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Affiliation(s)
- Aiko Sekita
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
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Tanaka M, Matsugaki A, Ishimoto T, Nakano T. Evaluation of crystallographic orientation of biological apatite in vertebral cortical bone in ovariectomized cynomolgus monkeys treated with minodronic acid and alendronate. J Bone Miner Metab 2016; 34:234-41. [PMID: 25837430 DOI: 10.1007/s00774-015-0658-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 02/01/2015] [Indexed: 10/23/2022]
Abstract
Quantitative analysis of the orientational distribution of biological apatite (BAp) crystals is proposed as a new index of bone quality. This study aimed to analyze BAp c-axis orientation in ovariectomized (OVX) monkeys treated with amino-bisphosphonates minodronic acid and alendronate as reference. Sixty female monkeys aged 9-17 years were divided into five groups: one sham group and four OVX groups. The sham group and one OVX group were treated daily with vehicle for 17 months. The other three groups were treated daily with minodronic acid at doses of 0.015 and 0.15 mg/kg, and alendronate at 0.5 mg/kg orally, respectively. The seventh lumbar vertebrae were subjected to analysis of the preferential BAp c-axis orientation in the ventral cortical bone. The BAp c-axis orientation along the craniocaudal axis was significantly increased in the OVX monkeys. The high dose of minodronic acid suppressed the OVX-induced increase in the BAp c-axis orientation, whereas alendronate showed a non-significant tendency to suppress the increase in the orientation. In analysis with other parameters, the BAp c-axis orientation was positively correlated with bone formation indices in biochemical markers and bone histomorphometry and negatively correlated with the increase in lumbar bone mineral density. On the other hand, the BAp c-axis orientation was not correlated with bone resorption indices, except for the eroded surface. These results indicate that the increase in BAp c-axis orientation was ameliorated by minodronic acid treatment in OVX monkeys, mainly by suppression of bone formation increase.
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Affiliation(s)
- Makoto Tanaka
- Research Promotion, Ono Pharmaceutical Co., Ltd., 3-1-1 Sakurai, Shimamoto, Osaka, 618-8585, Japan.
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
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26
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Iwasaki Y, Kazama JJ, Yamato H, Matsugaki A, Nakano T, Fukagawa M. Altered material properties are responsible for bone fragility in rats with chronic kidney injury. Bone 2015; 81:247-254. [PMID: 26187196 DOI: 10.1016/j.bone.2015.07.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 07/02/2015] [Accepted: 07/13/2015] [Indexed: 01/22/2023]
Abstract
Chronic kidney disease (CKD) is associated with an increased risk of fragility fractures, but the underlying pathophysiological mechanism remains obscure. We performed an in vivo experimental study to examine the roles of uremia and abnormal mineral/parathyroid metabolism in the development of bone metabolic abnormalities in uremic rats. Male Sprague-Dawley rats were divided into four groups, comprising sham operation (high turnover bone control=HTB-Cont), 5/6-nephrectomy (high turnover bone nephrectomized=HTB-Nx), thyroparathyroidectomy (low turnover bone control=LTB-Cont), and thyroparathyroidectomy plus 5/6 nephrectomy (low turnover bone nephrectomized=LTB-Nx), and maintained for 16 weeks. Uremia was successfully created in the LTB-Nx and HTB-Nx groups, while hyperparathyroidism was only found in the HTB-Nx group. Cancellous bone histomorphometry revealed significantly higher bone turnover in the HTB-Nx group than in the LTB-Nx group. Storage modulus at 1 Hz and tan delta in cortical bone of the femur, which represent the viscoelastic mechanical properties, were significantly lower in both Nx groups than in the Cont groups regardless of bone metabolism. Pentosidine-to-matrix ratio was increased and crystallinity was decreased in both Nx groups regardless of bone turnover. Mineral-to-matrix ratio was significantly decreased in the HTB-Nx group, but increased in the LTB-Nx group. Enzymatic collagen crosslinks were decreased in the HTB-Nx group. The degree of orientation of the c-axis in carbonated hydroxyapatite (biological apatite=BAp) crystallites was decreased in both Nx groups regardless of bone metabolism. Stepwise multivariate regression revealed that pentosodine-to-matrix ratio and BAp preferential c-axis orientation were significantly associated with storage modulus and tan delta. In conclusion, bone elastic mechanical properties deteriorated regardless of bone metabolism or bone mass in rats with chronic kidney injury. Various changes in bone mineral properties were associated with CKD, including abnormal parathyroid function, impaired bone turnover, and uremia associated with the accumulation of uremic toxins, were responsible for these changes. Pentosidine-to-matrix ratio and BAp orientation at position 5 were the two meaningful determinants of elastic bone mechanical strength, and both factors were associated with the severity of uremia, but not parathyroid function or bone metabolism. These two factors may account for the increased bone fragility among CKD patients.
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Affiliation(s)
- Yoshiko Iwasaki
- Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita, Japan
| | - Junichiro J Kazama
- Division of Blood Purification Therapy, Niigata University Medical and Dental Hospital, Niigata, Japan.
| | - Hideyuki Yamato
- Responsible Care Planning Division, Kureha Corporation, Iwaki, Japan
| | - Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Masafumi Fukagawa
- Division of Nephrology and Metabolism, Tokai University School of Medicine, Isehara, Japan
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Sathi GA, Kenmizaki K, Yamaguchi S, Nagatsuka H, Yoshida Y, Matsugaki A, Ishimoto T, Imazato S, Nakano T, Matsumoto T. Early initiation of endochondral ossification of mouse femur cultured in hydrogel with different mechanical stiffness. Tissue Eng Part C Methods 2015; 21:567-75. [PMID: 25381834 DOI: 10.1089/ten.tec.2014.0475] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mineralization is one of the most important processes in normal bone tissue development and in disease condition. Developing a novel and standardized in vitro model system that can readily monitor both cellular dynamics and mineralization is crucial for better understanding the bone tissue development and growth. Recent studies indicated that the mechanical environment is a critical condition in mineralization. We hypothesized that hydrogel with different mechanical stiffness can provide a biomimetic mechanical environment that can modulate bone tissue growth and mineralization. A femur of mouse embryo (embryonic day 16) was embedded in agarose hydrogel (2-60 kPa) and cultured in an osteogenic medium for a week. Microcomputed tomography (μCT) results revealed enhanced mineralization was detected in the femur head cultured in the gel condition, whereas no mineralization in the femur head cultured in the control (floating culture) condition. The mineralized region was corresponding to the region of secondary ossification center. Both histological and quantitative analyses indicated that the mineralized region of femur head cultured in 10 kPa gel condition was the highest and the mineralized area was significantly larger than that cultured in 2, 40, and 60 kPa gel condition. Immunofluorescence results indicated the enhanced mineralization caused by the higher chondrogenic differentiation at that region. This enhancement mainly relating to the mechanical forces and not to the oxygen tension was also confirmed. Since this system enhances and shortens the mineralization procedure compared with the conventional two-dimensional or three-dimensional cell culture system, this hydrogel system would be one of the unique models for better understanding the mineralized tissue development.
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Affiliation(s)
- Gulsan Ara Sathi
- 1Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | | | - Satoshi Yamaguchi
- 3Department of Biomaterials, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Hitoshi Nagatsuka
- 4Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Yasuhiro Yoshida
- 5Division of Oral Health Science, Department of Biomaterials and Bioengineering, Graduate School of Dental Medicine, Hokkaido University, Hokkaido, Japan
| | | | | | - Satoshi Imazato
- 3Department of Biomaterials, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | | | - Takuya Matsumoto
- 1Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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Matsugaki A, Aramoto G, Ninomiya T, Sawada H, Hata S, Nakano T. Abnormal arrangement of a collagen/apatite extracellular matrix orthogonal to osteoblast alignment is constructed by a nanoscale periodic surface structure. Biomaterials 2014; 37:134-43. [PMID: 25453944 DOI: 10.1016/j.biomaterials.2014.10.025] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [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: 07/30/2014] [Accepted: 10/02/2014] [Indexed: 10/24/2022]
Abstract
Morphological and directional alteration of cells is essential for structurally appropriate construction of tissues and organs. In particular, osteoblast alignment is crucial for the realization of anisotropic bone tissue microstructure. In this article, the orientation of a collagen/apatite extracellular matrix (ECM) was established by controlling osteoblast alignment using a surface geometry with nanometer-sized periodicity induced by laser ablation. Laser irradiation induced self-organized periodic structures (laser-induced periodic surface structures; LIPSS) with a spatial period equal to the wavelength of the incident laser on the surface of biomedical alloys of Ti-6Al-4V and Co-Cr-Mo. Osteoblast orientation was successfully induced parallel to the grating structure. Notably, both the fibrous orientation of the secreted collagen matrix and the c-axis of the produced apatite crystals were orientated orthogonal to the cell direction. To the best of our knowledge, this is the first report demonstrating that bone tissue anisotropy is controllable, including the characteristic organization of a collagen/apatite composite orthogonal to the osteoblast orientation, by controlling the cell alignment using periodic surface geometry.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Gento Aramoto
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takafumi Ninomiya
- Canon Machinery Inc., 85, Minami Yamada-cho, Kusatsu, Shiga 525-8511, Japan
| | - Hiroshi Sawada
- Canon Machinery Inc., 85, Minami Yamada-cho, Kusatsu, Shiga 525-8511, Japan
| | - Satoshi Hata
- Department of Electrical and Materials Science, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
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Matsugaki A, Isobe Y, Saku T, Nakano T. Quantitative regulation of bone-mimetic, oriented collagen/apatite matrix structure depends on the degree of osteoblast alignment on oriented collagen substrates. J Biomed Mater Res A 2014; 103:489-99. [PMID: 24733774 DOI: 10.1002/jbm.a.35189] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [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: 12/13/2013] [Revised: 03/19/2014] [Accepted: 03/26/2014] [Indexed: 11/09/2022]
Abstract
Bone tissue has a specific anisotropic morphology derived from collagen fiber alignment and the related apatite crystal orientation as a bone quality index. However, the precise mechanism of cellular regulation of the crystallographic orientation of apatite has not been clarified. In this study, anisotropic construction of cell-produced mineralized matrix in vitro was established by initiating organized cellular alignment and subsequent oriented bone-like matrix (collagen/apatite) production. The oriented collagen substrates with three anisotropic levels were prepared by a hydrodynamic method. Primary osteoblasts were cultured on the fabricated substrates until mineralized matrix formation is confirmed. Osteoblast alignment was successfully regulated by the level of substrate collagen orientation, with preferential alignment along the direction of the collagen fibers. Notably, both fibrous orientation of newly synthesized collagen matrix and c-axis of produced apatite crystals showed preferential orientation along the cell direction. Because the degree of anisotropy of the deposited apatite crystals showed dependency on the directional distribution of osteoblasts cultured on the oriented collagen substrates, the cell orientation determines the crystallographic anisotropy of produced apatite crystals. To the best of our knowledge, this is the first report demonstrating that bone tissue anisotropy, even the alignment of apatite crystals, is controllable by varying the degree of osteoblast alignment via regulating the level of substrate orientation.
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Affiliation(s)
- Aira Matsugaki
- Department of Materials Science and Engineering Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka, 565-0871, Japan
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Matsugaki A, Nakano T. [Anisotropic crystallization of biominerals]. Clin Calcium 2014; 24:193-202. [PMID: 24473352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bone tissue exhibits an oriented microstructure comprising apatite crystals and collagen fibers. The mechanical, biological and chemical properties of bone tissue represent the highly anisotropic feature depending on the degree of anisotropy in crystallographic structure of apatite. Preferred orientation of apatite crystals is one of the promising parameters which determine bone quality, because the bone mechanical function is dominated by the degree of apatite crystallographic orientation rather than bone mineral density. The anisotropic microstructure of bone tissue is regulated by the mutual activities of bone cells in response to the various kinds of environmental factors. In this report, we introduce the evaluation of bone quality based on the analysis of preferential orientation of apatite c-axis by using micro-beam XRD method and our recent research about cellular regulation of bone tissue anisotropy, especially focusing on the morphological changes of bone cells regulated by the microenvironment surrounding the cells.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Japan
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Hagihara K, Fujii K, Matsugaki A, Nakano T. Possibility of Mg- and Ca-based intermetallic compounds as new biodegradable implant materials. Materials Science and Engineering: C 2013; 33:4101-11. [DOI: 10.1016/j.msec.2013.05.055] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 05/04/2013] [Accepted: 05/30/2013] [Indexed: 01/04/2023]
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Matsugaki A, Fujiwara N, Nakano T. Continuous cyclic stretch induces osteoblast alignment and formation of anisotropic collagen fiber matrix. Acta Biomater 2013; 9:7227-35. [PMID: 23523937 DOI: 10.1016/j.actbio.2013.03.015] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 02/14/2013] [Accepted: 03/13/2013] [Indexed: 01/19/2023]
Abstract
Bone tissue geometry shows a highly anisotropic architecture, which is derived from its genetic regulation and mechanical environment. Osteoblasts are responsible not only for bone formation, through the secretion of collagen type I, but also for sensing the mechanical stimuli due to bone surface strain. Mechanotransduction by osteoblasts is therefore considered one of the regulators of anisotropic bone tissue morphogenesis. The orientation of osteoblasts and the secreted collagen matrix was successfully regulated by applying a continuous mechanical stress on osteoblasts for a long period. Under a continuous cyclic stretch of 4% magnitude at a rate of 2 cycles min(-1), osteoblasts reoriented their actin stress fibers in the direction that minimizes the strain applied to them. Extended culture of up to 2weeks resulted in the formation of collagen fibers in the extracellular spaces, and the preferred orientation of these fibers was parallel to the direction of cell elongation. To the best of our knowledge, this is the first report to establish anisotropic bone matrix architecture following the alignment of osteoblasts under mechanical stimuli for long-term cultivation.
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Affiliation(s)
- Aira Matsugaki
- Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871, Japan
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Matsugaki A, Aramoto G, Nakano T. The alignment of MC3T3-E1 osteoblasts on steps of slip traces introduced by dislocation motion. Biomaterials 2012; 33:7327-35. [PMID: 22818653 DOI: 10.1016/j.biomaterials.2012.06.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 06/15/2012] [Indexed: 01/07/2023]
Abstract
Bone tissue shows a highly anisotropic microstructure comprising biological apatite and collagen fibrils produced by the mutual activities of bone cells, which dominates its mechanical function. Accordingly, directional control of osteoblasts is crucial for forming anisotropic bone tissue. A new approach was proposed for controlling cell directionality by using crystallographic slip traces caused by dislocation glide. Dislocations were introduced into α-titanium single crystals by plastic deformation of (011¯0)[21¯1¯0] slip system, inducing a step-like structure with acute angles between the surface normal and the slip plane. Topographical properties of step patterning, including step interval and step height, could be controlled by varying the compressive plastic strain. The step geometry introduced by plastic deformation strongly influenced osteoblast elongation, and it aligned preferentially along slip traces. Ti substrates under 10% plastic strain with step height of approximately 300 nm and step interval of 10 μm induced osteoblast alignment most successfully. Actin stress fibers elongated parallel to slip traces, with polarized vinculin accumulation between steps.
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Affiliation(s)
- Aira Matsugaki
- Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan
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