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Schwartzman JD, McCall M, Ghattas Y, Pugazhendhi AS, Wei F, Ngo C, Ruiz J, Seal S, Coathup MJ. Multifunctional scaffolds for bone repair following age-related biological decline: Promising prospects for smart biomaterial-driven technologies. Biomaterials 2024; 311:122683. [PMID: 38954959 DOI: 10.1016/j.biomaterials.2024.122683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/09/2024] [Accepted: 06/23/2024] [Indexed: 07/04/2024]
Abstract
The repair of large bone defects due to trauma, disease, and infection can be exceptionally challenging in the elderly. Despite best clinical practice, bone regeneration within contemporary, surgically implanted synthetic scaffolds is often problematic, inconsistent, and insufficient where additional osteobiological support is required to restore bone. Emergent smart multifunctional biomaterials may drive important and dynamic cellular crosstalk that directly targets, signals, stimulates, and promotes an innate bone repair response following age-related biological decline and when in the presence of disease or infection. However, their role remains largely undetermined. By highlighting their mechanism/s and mode/s of action, this review spotlights smart technologies that favorably align in their conceivable ability to directly target and enhance bone repair and thus are highly promising for future discovery for use in the elderly. The four degrees of interactive scaffold smartness are presented, with a focus on bioactive, bioresponsive, and the yet-to-be-developed autonomous scaffold activity. Further, cell- and biomolecular-assisted approaches were excluded, allowing for contemporary examination of the capabilities, demands, vision, and future requisites of next-generation biomaterial-induced technologies only. Data strongly supports that smart scaffolds hold significant promise in the promotion of bone repair in patients with a reduced osteobiological response. Importantly, many techniques have yet to be tested in preclinical models of aging. Thus, greater clarity on their proficiency to counteract the many unresolved challenges within the scope of aging bone is highly warranted and is arguably the next frontier in the field. This review demonstrates that the use of multifunctional smart synthetic scaffolds with an engineered strategy to circumvent the biological insufficiencies associated with aging bone is a viable route for achieving next-generation therapeutic success in the elderly population.
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Affiliation(s)
| | - Max McCall
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Yasmine Ghattas
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Abinaya Sindu Pugazhendhi
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Fei Wei
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Christopher Ngo
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Jonathan Ruiz
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Sudipta Seal
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA; Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), Materials Science and Engineering, College of Medicine, University of Central Florida, USA, Orlando, FL
| | - Melanie J Coathup
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA.
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Vahidi G, Boone C, Hoffman F, Heveran C. Aging decreases osteocyte peri-lacunar-canalicular system turnover in female C57BL/6JN mice. Bone 2024; 186:117163. [PMID: 38857854 PMCID: PMC11227388 DOI: 10.1016/j.bone.2024.117163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 06/06/2024] [Accepted: 06/07/2024] [Indexed: 06/12/2024]
Abstract
Osteocytes engage in bone resorption and mineralization surrounding their expansive lacunar-canalicular system (LCS) through peri-LCS turnover. However, fundamental questions persist about where, when, and how often osteocytes engage in peri-LCS turnover and how these processes change with aging. Furthermore, whether peri-LCS turnover is associated with natural variation in cortical tissue strain remains unexplored. To address these questions, we utilized confocal scanning microscopy, immunohistochemistry, and scanning electron microscopy to characterize osteocyte peri-LCS turnover in the cortical (mid-diaphysis) and cancellous (metaphysis) regions of femurs from young adult (5 mo) and early-old-age (22 mo) female C57BL/6JN mice. LCS bone mineralization was measured by the presence of perilacunar fluorochrome labels. LCS bone resorption was measured by immunohistochemical marker of bone resorption. The dynamics of peri-LCS turnover were estimated from serial fluorochrome labeling, where each mouse was administered two labels between 2 and 16 days before euthanasia. Osteocyte participation in mineralizing their surroundings is highly abundant in both cortical and cancellous bone of young adult mice but significantly decreases with aging. LCS bone resorption also decreases with aging. Aging has a greater impact on peri-LCS turnover dynamics in cancellous bone than in cortical bone. Lacunae with recent peri-LCS turnover are larger in both age groups. While peri-LCS turnover is associated with variation in tissue strain between cortical quadrants and intracortical location for 22 mo mice, these associations were not seen for 5 mo mice. The impact of aging on decreasing peri-LCS turnover may have significant implications for bone quality and mechanosensation.
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Affiliation(s)
- Ghazal Vahidi
- Department of Mechanical & Industrial Engineering, Montana State University, Bozeman, MT, USA
| | - Connor Boone
- Department of Mechanical & Industrial Engineering, Montana State University, Bozeman, MT, USA
| | - Fawn Hoffman
- Department of Biomedical Sciences, College of Idaho, Caldwell, ID, USA
| | - Chelsea Heveran
- Department of Mechanical & Industrial Engineering, Montana State University, Bozeman, MT, USA.
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3
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Moreno-Jiménez I, Heinig S, Heras U, Maichl DS, Strifler S, Leich E, Blouin S, Fratzl P, Fratzl-Zelman N, Jundt F, Cipitria A. 3D osteocyte lacunar morphometry of human bone biopsies with high resolution microCT: From monoclonal gammopathy to newly diagnosed multiple myeloma. Bone 2024:117236. [PMID: 39151745 DOI: 10.1016/j.bone.2024.117236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 07/26/2024] [Accepted: 08/13/2024] [Indexed: 08/19/2024]
Abstract
Osteocytes are mechanosensitive, bone-embedded cells which are connected via dendrites in a lacuno-canalicular network and regulate bone resorption and formation balance. Alterations in osteocyte lacunar volume, shape and density have been identified in conditions of aging, osteoporosis and osteolytic bone metastasis, indicating patterns of impaired bone remodeling, osteolysis and disease progression. Osteolytic bone disease is a hallmark of the hematologic malignancy multiple myeloma (MM), in which monoclonal plasma cells in the bone marrow disrupt the bone homeostasis and induce excessive resorption at local and distant sites. Qualitative and quantitative changes in the 3D osteocyte lacunar morphometry have not yet been evaluated in MM, nor in the precursor conditions monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM). In this study, we characterized the osteocyte lacunar morphology in trabecular bone of the iliac crest at the ultrastructural level using high resolution microCT in human bone biopsy samples of three MGUS, two SMM and six newly diagnosed MM. In MGUS, SMM and MM we found a trend for lower lacunar density and a shift towards larger lacunae with disease progression (higher 50 % cutoff of the lacunar volume cumulative distribution) in the small osteocyte lacunae 20-900 μm3 range compared to control samples. In the larger lacunae 900-3000 μm3 range, we detected significantly higher lacunar density and microporosity in the MM group compared to the MGUS/SMM group. Regarding the shape distribution, the MGUS/SMM group showed a trend for flatter, more elongated and anisotropic osteocyte lacunae compared to the control group. Altogether, our findings suggest that osteocytes in human MM bone disease undergo changes in their lacunae density, volume and shape, which could be an indicator for osteolysis and disease progression. Future studies are needed to understand whether alterations of the lacunae architecture affect the mechanoresponsiveness of osteocytes and ultimately bone adaptation and fracture resistance in MM and its precursors conditions.
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Affiliation(s)
- Inés Moreno-Jiménez
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476 Potsdam, Germany.
| | - Sharen Heinig
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476 Potsdam, Germany
| | - Unai Heras
- Group of Bioengineering in Regeneration and Cancer, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain; Department of Cell Biology and Histology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, 48940 Leioa, Spain
| | - Daniela Simone Maichl
- Department of Internal Medicine II, University Hospital Würzburg, 97080 Würzburg, Germany
| | - Susanne Strifler
- Department of Internal Medicine II, University Hospital Würzburg, 97080 Würzburg, Germany
| | - Ellen Leich
- Institute of Pathology, University of Würzburg, 97080 Würzburg, Germany; Comprehensive Cancer Center Mainfranken, 97080 Würzburg, Germany
| | - Stéphane Blouin
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, Vienna, Austria
| | - Peter Fratzl
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476 Potsdam, Germany
| | - Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, Vienna, Austria
| | - Franziska Jundt
- Department of Internal Medicine II, University Hospital Würzburg, 97080 Würzburg, Germany; Comprehensive Cancer Center Mainfranken, 97080 Würzburg, Germany.
| | - Amaia Cipitria
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476 Potsdam, Germany; Group of Bioengineering in Regeneration and Cancer, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain; IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain.
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4
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Hande SS, Andronowski JM, Miller EH. Microarchitecture of the penis bone (baculum) of a seal: A 3D morphometric examination using synchrotron and laboratory micro-computed tomography. Anat Rec (Hoboken) 2024; 307:2858-2874. [PMID: 38311971 DOI: 10.1002/ar.25396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/08/2024] [Accepted: 01/13/2024] [Indexed: 02/06/2024]
Abstract
We examined the ultrastructure of the mammalian os penis at the high-resolution synchrotron level. Previously, bacular microanatomy had only been investigated histologically. We studied the baculum of the harp seal (Pagophilus groenlandicus), in which the baculum varies more in size and shape than does a mechanically constrained bone (humerus). We (1) investigated the microarchitecture of bacula and humeri from the same seal specimens, and (2) described changes in bone micro- and macro-morphology associated with age (n = 15, age range = 1-35 years) and bone type. We analyzed cross-sectional geometry non-destructively through laboratory micro-computed tomography. We suggest that the midshaft may resist axial compression while the proximal region may resist torsion, based on measurements of cross-sectional and cortical areas, perimeter, ratio of maximum and minimum moments of inertia, and polar moment of inertia. In addition, midshaft bacula may be less mechanosensitive than humeri, based on microstructural variables (e.g., volume, surface area, diameter associated with lacunae and cortical porosity) analyzed across age groupings. Our findings related to the microarchitecture of the pinniped baculum provide a basis for further studies on development, mechanical properties, functions, and adaptations in this and other pinniped species. Our use of a multi-modal imaging approach was minimally destructive for reproducible and accurate comparison of three-dimensional bone ultrastructure. Such methods, coupled with multidisciplinary analyses, enable diverse studies of bone biology, life history, and evolution using museum collections.
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Affiliation(s)
- Shreya S Hande
- Department of Biology, Memorial University of Newfoundland, Canada
| | - Janna M Andronowski
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, Canada
| | - Edward H Miller
- Department of Biology, Memorial University of Newfoundland, Canada
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5
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Yu B, Gauthier R, Olivier C, Villanova J, Follet H, Mitton D, Peyrin F. 3D quantification of the lacunocanalicular network on human femoral diaphysis through synchrotron radiation-based nanoCT. J Struct Biol 2024; 216:108111. [PMID: 39059753 DOI: 10.1016/j.jsb.2024.108111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 07/09/2024] [Accepted: 07/22/2024] [Indexed: 07/28/2024]
Abstract
Osteocytes are the major actors in bone mechanobiology. Within bone matrix, they are trapped close together in a submicrometric interconnected network: the lacunocanalicular network (LCN). The interstitial fluid circulating within the LCN transmits the mechanical information to the osteocytes that convert it into a biochemical signal. Understanding the interstitial fluid dynamics is necessary to better understand the bone mechanobiology. Due to the submicrometric dimensions of the LCN, making it difficult to experimentally investigate fluid dynamics, numerical models appear as a relevant tool for such investigation. To develop such models, there is a need for geometrical and morphological data on the human LCN. This study aims at providing morphological data on the human LCN from measurement of 27 human femoral diaphysis bone samples using synchrotron radiation nano-computed tomography with an isotropic voxel size of 100 nm. Except from the canalicular diameter, the canalicular morphological parameters presented a high variability within one sample. Some differences in terms of both lacunar and canalicular morphology were observed between the male and female populations. But it has to be highlighted that all the canaliculi cannot be detected with a voxel size of 100 nm. Hence, in the current study, only a specific population of large canaliculi that could be characterize. Still, to the authors knowledge, this is the first time such a data set was introduced to the community. Further processing will be achieved in order to provide new insight on the LCN permeability.
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Affiliation(s)
- Boliang Yu
- Univ Lyon, INSA Lyon, Universite Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS UMR 5220, Inserm U1206, CREATIS, 69621 Lyon, France
| | - Remy Gauthier
- CNRS, INSA Lyon, Universite Claude Bernard Lyon 1 UCBL, MATEIS UMR CNRS 5510, Bât. Saint Exupéry, 23 Av. Jean Capelle, F-69621 Villeurbanne, France.
| | - Cécile Olivier
- Université Grenoble Alpes, Institut National de la Santé et de la Recherche Médicale, UA7 Synchrotron Radiation for Biomedicine, Saint-Martin d'Hères, France
| | | | - Hélène Follet
- Univ Lyon, Universite Claude Bernard Lyon 1, INSERM, LYOS UMR1033, Lyon, France
| | - David Mitton
- Univ Lyon, Univ Gustave Eiffel, Universite Claude Bernard Lyon 1, LBMC UMR_T9406, 69622 Lyon, France
| | - Francoise Peyrin
- Univ Lyon, INSA Lyon, Universite Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS UMR 5220, Inserm U1206, CREATIS, 69621 Lyon, France
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6
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de Gruchy YA, Faillace KE, Van de Vijver K, Schotsmans EMJ, Seifert J, Bricking A, Nederbragt AJ, Madgwick R. Bone of contention: Intra-element variability in remodelling of human femora based on histomorphometric and isotope analyses. PLoS One 2024; 19:e0305089. [PMID: 38923938 PMCID: PMC11207156 DOI: 10.1371/journal.pone.0305089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 05/22/2024] [Indexed: 06/28/2024] Open
Abstract
The volume of human carbon (δ13C) and nitrogen (δ15N) isotope data produced in archaeological research has increased markedly in recent years. However, knowledge of bone remodelling, its impact on isotope variation, and the temporal resolution of isotope data remains poorly understood. Varied remodelling rates mean different elements (e.g., femur and rib) produce different temporal signals but little research has examined intra-element variability. This study investigates human bone remodelling using osteon population density and the relationship with carbon and nitrogen isotope data at a high resolution, focusing on variation through femoral cross-sections, from periosteal to endosteal surfaces. Results demonstrate considerable differences in isotope values between cross-sectional segments of a single fragment, by up to 1.3‰ for carbon and 1.8‰ for nitrogen, illustrating the need for standardised sampling strategies. Remodelling also varies between bone sections, occurring predominantly within the endosteal portion, followed by the midcortical and periosteal. Therefore, the endosteal portion likely reflects a shorter period of life closer to the time of death, consistent with expectations. By contrast, the periosteal surface provides a longer average, though there were exceptions to this. Results revealed a weak negative correlation between osteon population density and δ15N or δ13C, confirming that remodelling has an effect on isotope values but is not the principal driver. However, a consistent elevation of δ15N and δ13C (0.5‰ average) was found between the endosteal and periosteal regions, which requires further investigation. These findings suggest that, with further research, there is potential for single bone fragments to reconstruct in-life dietary change and mobility, thus reducing destructive sampling.
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Affiliation(s)
- Yasmine A. de Gruchy
- School of History, Archaeology and Religion, Cardiff University, Cardiff, United Kingdom
| | - Katie E. Faillace
- School of History, Archaeology and Religion, Cardiff University, Cardiff, United Kingdom
| | | | | | - Jerrod Seifert
- School of History, Archaeology and Religion, Cardiff University, Cardiff, United Kingdom
| | - Adelle Bricking
- School of History, Archaeology and Religion, Cardiff University, Cardiff, United Kingdom
- Amgueddfa Cymru–Museum Wales, Cardiff, United Kingdom
| | | | - Richard Madgwick
- School of History, Archaeology and Religion, Cardiff University, Cardiff, United Kingdom
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7
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Sefa S, Espiritu J, Ćwieka H, Greving I, Flenner S, Will O, Beuer S, Wieland DF, Willumeit-Römer R, Zeller-Plumhoff B. Multiscale morphological analysis of bone microarchitecture around Mg-10Gd implants. Bioact Mater 2023; 30:154-168. [PMID: 37575877 PMCID: PMC10412723 DOI: 10.1016/j.bioactmat.2023.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 07/07/2023] [Accepted: 07/20/2023] [Indexed: 08/15/2023] Open
Abstract
The utilization of biodegradable magnesium (Mg)-based implants for restoration of bone function following trauma represents a transformative approach in orthopaedic application. One such alloy, magnesium-10 weight percent gadolinium (Mg-10Gd), has been specifically developed to address the rapid degradation of Mg while enhancing its mechanical properties to promote bone healing. Previous studies have demonstrated that Mg-10Gd exhibits favorable osseointegration; however, it exhibits distinct ultrastructural adaptation in comparison to conventional implants like titanium (Ti). A crucial aspect that remains unexplored is the impact of Mg-10Gd degradation on the bone microarchitecture. To address this, we employed hierarchical three-dimensional imaging using synchrotron radiation in conjunction with image-based finite element modelling. By using the methods outlined, the vascular porosity, lacunar porosity and the lacunar-canaliculi network (LCN) morphology of bone around Mg-10Gd in comparison to Ti in a rat model from 4 weeks to 20 weeks post-implantation was investigated. Our investigation revealed that within our observation period, the degradation of Mg-10Gd implants was associated with significantly lower (p < 0.05) lacunar density in the surrounding bone, compared to Ti. Remarkably, the LCN morphology and the fluid flow analysis did not significantly differ for both implant types. In summary, a more pronounced lower lacunae distribution rather than their morphological changes was detected in the surrounding bone upon the degradation of Mg-10Gd implants. This implies potential disparities in bone remodelling rates when compared to Ti implants. Our findings shed light on the intricate relationship between Mg-10Gd degradation and bone microarchitecture, contributing to a deeper understanding of the implications for successful osseointegration.
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Affiliation(s)
- Sandra Sefa
- Institute of Metallic Biomaterials, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | | | - Hanna Ćwieka
- Institute of Metallic Biomaterials, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | - Imke Greving
- Institute of Materials Physics, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | - Silja Flenner
- Institute of Materials Physics, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | - Olga Will
- Molecular Imaging North Competence Center, Kiel University, Kiel, Germany
| | - Susanne Beuer
- Fraunhofer Institut für Integrierte Systeme und Bauelementetechnologie (IISB), Erlangen, Germany
| | - D.C Florian Wieland
- Institute of Metallic Biomaterials, Helmholtz Zentrum Hereon, Geesthacht, Germany
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8
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Ahmed F, Minamizaki T, Aubin JE, Damayanti MA, Yoshiko Y. Large scale analysis of osteocyte lacunae in klotho hypomorphic mice using high-resolution micro-computed tomography. Ann Anat 2023; 250:152142. [PMID: 37572763 DOI: 10.1016/j.aanat.2023.152142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 07/14/2023] [Accepted: 07/26/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND Osteocytes are the most abundant cell type in adult bone, and the morphological characteristics of osteocytes and their lacunae appear to influence bone mass and fragility. Although conventional computed tomography (CT) has contributed greatly to advances in bone morphometry, capturing details of the entire hierarchical assembly, e.g., osteocyte lacuna parameters, has been limited by the analytical performance of CT (> 1 µm resolution). METHODS We used high-resolution (700 nm) micro-CT to evaluate and compare the osteocyte lacuna parameters over a large scale, i.e., in a maximum of about 45,700 lacunae (average), in tibial metaphyseal cortical bones of wild-type (WT) and αKlotho-hypomorphic (kl/kl) mice, the latter a model that exhibits osteopenia and aberrant osteocytes. RESULTS Of osteocyte lacuna parameters, lacunar surface per lacunar volume were significantly lower and lacuna diameter were significantly larger in kl/kl mice compared to WT mice. By analysis of individual osteocyte lacunae, we found that lacunar sphericity in kl/kl mice was higher than that in WT mice, and the diameters in the major and the minor axes were respectively lower and higher in kl/kl mice, especially at the proximal site of the region of interest. CONCLUSION We successfully assessed osteocyte lacuna parameters on the largest scale in mice reported to date and found that the shape of osteocyte lacunae of kl/kl mice are significantly different from those of WT mice. Although the mechanisms underlying the lacunar shape differences observed are not yet clear, changes in lacunar geometry are known to affect the transitions of strains to the osteocyte microenvironment and likely local osteocyte response(s). Thus, the fact that the differences are limited to the mesial region near the primary spongiosa suggests the likelihood of site-specific anomalies in mechanosensitive effects in kl/kl osteocytes with consequent site-specific effects bone metabolism and function.
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Affiliation(s)
- Faisal Ahmed
- Department of Calcified Tissue Biology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan
| | - Tomoko Minamizaki
- Department of Calcified Tissue Biology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan
| | - Jane E Aubin
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Merry Annisa Damayanti
- Department of Calcified Tissue Biology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan; Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Padjadjaran University, Bandung, Indonesia
| | - Yuji Yoshiko
- Department of Calcified Tissue Biology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
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9
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Nile M, Folwaczny M, Wichelhaus A, Baumert U, Janjic Rankovic M. Fluid flow shear stress and tissue remodeling-an orthodontic perspective: evidence synthesis and differential gene expression network analysis. Front Bioeng Biotechnol 2023; 11:1256825. [PMID: 37795174 PMCID: PMC10545883 DOI: 10.3389/fbioe.2023.1256825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 08/28/2023] [Indexed: 10/06/2023] Open
Abstract
Introduction: This study aimed to identify and analyze in vitro studies investigating the biological effect of fluid-flow shear stress (FSS) on cells found in the periodontal ligament and bone tissue. Method: We followed the PRISMA guideline for systematic reviews. A PubMed search strategy was developed, studies were selected according to predefined eligibility criteria, and the risk of bias was assessed. Relevant data related to cell source, applied FSS, and locus-specific expression were extracted. Based on this evidence synthesis and, as an original part of this work, analysis of differential gene expression using over-representation and network-analysis was performed. Five relevant publicly available gene expression datasets were analyzed using gene set enrichment analysis (GSEA). Result: A total of 6,974 articles were identified. Titles and abstracts were screened, and 218 articles were selected for full-text assessment. Finally, 120 articles were included in this study. Sample size determination and statistical analysis related to methodological quality and the ethical statement item in reporting quality were most frequently identified as high risk of bias. The analyzed studies mostly used custom-made fluid-flow apparatuses (61.7%). FSS was most frequently applied for 0.5 h, 1 h, or 2 h, whereas FSS magnitudes ranged from 6 to 20 dyn/cm2 depending on cell type and flow profile. Fluid-flow frequencies of 1 Hz in human cells and 1 and 5 Hz in mouse cells were mostly applied. FSS upregulated genes/metabolites responsible for tissue formation (AKT1, alkaline phosphatase, BGLAP, BMP2, Ca2+, COL1A1, CTNNB1, GJA1, MAPK1/MAPK3, PDPN, RUNX2, SPP1, TNFRSF11B, VEGFA, WNT3A) and inflammation (nitric oxide, PGE-2, PGI-2, PTGS1, PTGS2). Protein-protein interaction networks were constructed and analyzed using over-representation analysis and GSEA to identify shared signaling pathways. Conclusion: To our knowledge, this is the first review giving a comprehensive overview and discussion of methodological technical details regarding fluid flow application in 2D cell culture in vitro experimental conditions. Therefore, it is not only providing valuable information about cellular molecular events and their quantitative and qualitative analysis, but also confirming the reproducibility of previously published results.
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Affiliation(s)
- Mustafa Nile
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Munich, Germany
| | - Matthias Folwaczny
- Department of Conservative Dentistry and Periodontology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Andrea Wichelhaus
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Munich, Germany
| | - Uwe Baumert
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Munich, Germany
| | - Mila Janjic Rankovic
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Munich, Germany
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10
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Wüster J, Hesse B, Rothweiler R, Bortel E, Gross C, Bakhtiyari S, King A, Boller E, Gerber J, Rendenbach C, Fretwurst T, Preissner S, Heiland M, Nelson K, Nahles S. Comparison of the 3D-microstructure of human alveolar and fibula bone in microvascular autologous bone transplantation: a synchrotron radiation μ-CT study. Front Bioeng Biotechnol 2023; 11:1169385. [PMID: 37691907 PMCID: PMC10486015 DOI: 10.3389/fbioe.2023.1169385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 08/01/2023] [Indexed: 09/12/2023] Open
Abstract
Introduction: Autologous bone transplantation is successfully used in reconstructive surgery of large/critical-sized bone defects, whereby the microvascular free fibula flap is still regarded as the gold standard for the reconstruction of such defects in the head and neck region. Here, we report the morphological and lacunar properties of patient-paired bone samples from eight patients from the jaw (AB; recipient site) and the fibula (FB; donor site) on the micron length-scale using Synchrotron µ-CT. Insights into differences and similarities between these bone structures could offer a better understanding of the underlying mechanism for successful surgical outcomes and might clear the path for optimized, nature-inspired bone scaffold designs. Methods: Spatial vessel-pore arrangements, bone morphology, fluid-simulation derived permeability tensor, osteocyte lacunar density, and lacunar morphology are compared. Results: The orientation of the vessel system indicates a homogenous vessel orientation for AB and FB. The average mineral distance (50%) to the closest vessel boundary is higher in AB than in FB (the mean is 96 μm for AB vs. 76 μm for FB; p = 0.021). Average osteocyte lacunar density is found to be higher in AB than in FB (mean 22,874 mm3 vs. 19,376 mm3 for FB; p = 0.038), which might compensate for the high distance from the mineral to the nearest vessel. No significant differences in lacunar volume are found between paired AB and FB. Discussion: A comparable vessel network and similar distribution of vessel porosity between AB and FB may allow the FB graft to exhibit a high regeneration potential when connected to AB, and this might correlate with a high osteoinductive and osteoconductive potential of FB when connected to AB. Since widely used and potent synthetic bone grafts exist, new insight into the bone structure of well-established autologous bone grafts, such as the free fibula flap, could help to improve the performance of such materials and therefore the design of 3D scaffolds.
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Affiliation(s)
- Jonas Wüster
- Department of Oral and Maxillofacial Surgery, Berlin Institute of Health, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Bernhard Hesse
- Xploraytion GmbH, Berlin, Germany
- European Synchrotron Radiation Facility, Grenoble, France
| | - Rene Rothweiler
- Department of Oral- and Craniomaxillofacial Surgery, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | | | - Christian Gross
- Department of Oral- and Craniomaxillofacial Surgery, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | | | | | - Elodie Boller
- European Synchrotron Radiation Facility, Grenoble, France
| | | | - Carsten Rendenbach
- Department of Oral and Maxillofacial Surgery, Berlin Institute of Health, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Tobias Fretwurst
- Department of Oral- and Craniomaxillofacial Surgery, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | - Saskia Preissner
- Department of Oral and Maxillofacial Surgery, Berlin Institute of Health, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Max Heiland
- Department of Oral and Maxillofacial Surgery, Berlin Institute of Health, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Katja Nelson
- Department of Oral- and Craniomaxillofacial Surgery, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | - Susanne Nahles
- Department of Oral and Maxillofacial Surgery, Berlin Institute of Health, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
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11
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Ji C, Zhang L, Wang Y, Lin B, Bai X, Yun S, He B. The influence of different shaped osteocyte lacunae on microcrack initiation and propagation. Clin Biomech (Bristol, Avon) 2023; 108:106072. [PMID: 37611387 DOI: 10.1016/j.clinbiomech.2023.106072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/12/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND The morphology of osteocyte lacunae varies in bones of different ages and bone pathologies. Osteocyte lacunae can cause stress concentration and initiate microcracks. However, the influence of changes in osteocyte lacunar shape on microcrack is unknown. Therefore, the aim of this study was to determine the effects of osteocyte lacunae with different shapes on microcrack initiation and propagation. METHODS Osteon models containing osteocyte lacunae with different shapes were established. The progressive damage analysis method, based on computer simulations, was used to study the evolution of microdamage within the osteon, including the processes of intralaminar and interlaminar microdamage. FINDINGS Models with larger DoE values can effectively delay or prevent the formation of linear microcracks, which ensures high fracture toughness of cortical bone. It is subjected to stronger mechanical stimulation, making it more sensitive to loads. Models with smaller DoE values increase the load threshold for microdamage generation and reduces its impact on bone mechanical performance, making it less susceptible to microdamage than models with larger DoE values. INTERPRETATION These findings enhance the limited knowledge of the influence of the lacunar shape on microdamage and contribute to a better understanding of bone biomechanics.
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Affiliation(s)
- Chunhui Ji
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China
| | - Liang Zhang
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China
| | - Yan Wang
- Tianjin Hospital, Tianjin University, Tianjin 300072, PR China
| | - Bin Lin
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China.
| | - Xinlei Bai
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China
| | - Shiyue Yun
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China
| | - Bingnan He
- School of Mechanical Engineering, Tianjin University, Tianjin 300072, PR China
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12
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Buccino F, Zagra L, Longo E, D'Amico L, Banfi G, Berto F, Tromba G, Vergani LM. Osteoporosis and Covid-19: Detected similarities in bone lacunar-level alterations via combined AI and advanced synchrotron testing. MATERIALS & DESIGN 2023; 231:112087. [PMID: 37323219 PMCID: PMC10257887 DOI: 10.1016/j.matdes.2023.112087] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/03/2023] [Accepted: 06/09/2023] [Indexed: 06/17/2023]
Abstract
While advanced imaging strategies have improved the diagnosis of bone-related pathologies, early signs of bone alterations remain difficult to detect. The Covid-19 pandemic has brought attention to the need for a better understanding of bone micro-scale toughening and weakening phenomena. This study used an artificial intelligence-based tool to automatically investigate and validate four clinical hypotheses by examining osteocyte lacunae on a large scale with synchrotron image-guided failure assessment. The findings indicate that trabecular bone features exhibit intrinsic variability related to external loading, micro-scale bone characteristics affect fracture initiation and propagation, osteoporosis signs can be detected at the micro-scale through changes in osteocyte lacunar features, and Covid-19 worsens micro-scale porosities in a statistically significant manner similar to the osteoporotic condition. Incorporating these findings with existing clinical and diagnostic tools could prevent micro-scale damages from progressing into critical fractures.
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Affiliation(s)
- Federica Buccino
- Department of Mechanical Engineering, Politecnico di Milano, 20156, Italy
| | - Luigi Zagra
- I.R.C.C.S Ospedale Galeazzi - Sant'Ambrogio, Milano 20157, Italy
| | - Elena Longo
- Elettra-Sincrotrone Trieste SCpA, Basovizza, Trieste 34149, Italy
| | - Lorenzo D'Amico
- Elettra-Sincrotrone Trieste SCpA, Basovizza, Trieste 34149, Italy
| | - Giuseppe Banfi
- I.R.C.C.S Ospedale Galeazzi - Sant'Ambrogio, Milano 20157, Italy
| | - Filippo Berto
- Università La Sapienza, Rome 00185, Italy
- NTNU, Norway
| | - Giuliana Tromba
- Elettra-Sincrotrone Trieste SCpA, Basovizza, Trieste 34149, Italy
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13
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Sang W, Ural A. Evaluating the Role of Canalicular Morphology and Perilacunar Region Properties on Local Mechanical Environment of Lacunar-Canalicular Network Using Finite Element Modeling. J Biomech Eng 2023; 145:1156059. [PMID: 36629002 DOI: 10.1115/1.4056655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 01/07/2023] [Indexed: 01/12/2023]
Abstract
Physiological and pathological processes such as aging, diseases, treatments, and lactation can alter lacunar-canalicular network (LCN) morphology and perilacunar region properties. These modifications can impact the mechanical environment of osteocytes which in turn can influence osteocyte mechanosensitivity and the remodeling process. In this study, we aim to evaluate how the modifications in the canalicular morphology, lacunar density, and the perilacunar region properties influence the local mechanical environment of LCN and the apparent bone properties using three-dimensional finite element (FE) modeling. The simulation results showed that a 50% reduction in perilacunar elastic modulus led to about 7% decrease in apparent elastic modulus of the bone. The increase in canalicular density, length, and diameter did not influence the strain amplification in the models but they increased the amount of highly strained bone around LCN. Change in lacunar density did not influence the strain amplification and the amount of highly strained regions on LCN surfaces. Reduction in perilacunar elastic modulus increased both the strain amplification and the volume of highly strained tissue around and on the surface of LCN. The FE models of LCN in this study can be utilized to quantify the influence of modifications in canalicular morphology, lacunar density, and perilacunar region properties on the apparent bone properties and the local mechanical environment of LCN. Although this is a numerical study with idealized models, it provides important information on how mechanical environment of osteocytes is influenced by the modifications in LCN morphology and perilacunar region properties due to physiological and pathological processes.
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Affiliation(s)
- Wen Sang
- Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085
| | - Ani Ural
- Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085
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14
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Andronowski JM, Cole ME, Davis RA, Tubo GR, Taylor JT, Cooper DML. A multimodal 3D imaging approach of pore networks in the human femur to assess age-associated vascular expansion and Lacuno-Canalicular reduction. Anat Rec (Hoboken) 2023; 306:475-493. [PMID: 36153809 DOI: 10.1002/ar.25089] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/26/2022] [Accepted: 09/20/2022] [Indexed: 11/08/2022]
Abstract
Cellular communication in the mechanosensory osteocyte Lacuno-Canalicular Network (LCN) regulates bone tissue remodeling throughout life. Age-associated declines in LCN size and connectivity dysregulate mechanosensitivity to localized remodeling needs of aging or damaged tissue, compromising bone quality. Synchrotron radiation-based micro-Computed Tomography (SRμCT) and Confocal Laser Scanning Microscopy (CLSM) were employed to visualize LCN and vascular canal morphometry in an age series of the anterior femur (males n = 14, females n = 11, age range = 19-101, mean age = 55). Age-associated increases in vascular porosity were driven by pore coalescence, including a significant expansion in pore diameter and a significant decline in pore density. In contrast, the LCN showed significant age-associated reductions in lacunar volume fraction, mean diameter, and density, and in canalicular volume fraction and connectivity density. Lacunar density was significantly lower in females across the lifespan, exacerbating their age-associated decline. Canalicular connectivity density was also significantly lower in females but approached comparable declining male values in older age. Our data illuminate the trajectory and potential morphometric sources of age-associated bone loss. Increased vascular porosity contributes to bone fragility with aging, while an increasingly reduced and disconnected LCN undermines the mechanosensitivity required to repair and reinforce bone. Understanding why and how this degradation occurs is essential for improving the diagnosis and treatment of age-related changes in bone quality and fragility.
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Affiliation(s)
- Janna M Andronowski
- Faculty of Medicine, Division of BioMedical Sciences, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Mary E Cole
- Department of Biology, The University of Akron, Akron, Ohio, USA
| | - Reed A Davis
- Department of Biology, The University of Akron, Akron, Ohio, USA
| | - Gina R Tubo
- Northeast Ohio Medical University, Rootstown, Ohio, USA
| | - Joshua T Taylor
- Faculty of Medicine, Division of BioMedical Sciences, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - David M L Cooper
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, College of Medicine, Saskatoon, Saskatchewan, Canada
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15
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Blouin S, Misof BM, Mähr M, Fratzl-Zelman N, Roschger P, Lueger S, Messmer P, Keplinger P, Rauch F, Glorieux FH, Berzlanovich A, Gruber GM, Brugger PC, Shane E, Recker RR, Zwerina J, Hartmann MA. Osteocyte lacunae in transiliac bone biopsy samples across life span. Acta Biomater 2023; 157:275-287. [PMID: 36549635 DOI: 10.1016/j.actbio.2022.11.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 12/23/2022]
Abstract
Osteocytes act as bone mechanosensors, regulators of osteoblast/osteoclast activity and mineral homeostasis, however, knowledge about their functional/morphological changes throughout life is limited. We used quantitative backscattered electron imaging (qBEI) to investigate osteocyte lacunae sections (OLS) as a 2D-surrogate characterizing the osteocytes. OLS characteristics, the density of mineralized osteocyte lacunae (i.e., micropetrotic osteocytes, md.OLS-Density in nb/mm2) and the average degree of mineralization (CaMean in weight% calcium) of cortex and spongiosa were analyzed in transiliac biopsy samples from healthy individuals under 30 (n=59) and over 30 years (n=50) (i.e., before and after the age of peak bone mass, respectively). We found several differences in OLS-characteristics: 1). Inter-individually between the age groups: OLS-Density and OLS-Porosity were reduced by about 20% in older individuals in spongiosa and in cortex versus younger probands (both, p < 0.001). 2). Intra-individually between bone compartments: OLS-Density was higher in the cortex, +18.4%, p < 0.001 for younger and +7.6%, p < 0.05 for older individuals. Strikingly, the most frequent OLS nearest-neighbor distance was about 30 µm in both age groups and at both bone sites revealing a preferential organization of osteocytes in clusters. OLS-Density was negatively correlated with CaMean in both spongiosa and cortex (both, p < 0.001). Few mineralized OLS were found in young individuals along with an increase of md.OLS-Density with age. In summary, this transiliac bone sample analysis of 200000 OLS from 109 healthy individuals throughout lifespan reveals several age-related differences in OLS characteristics. Moreover, our study provides reference data from healthy individuals for different ages to be used for diagnosis of bone abnormalities in diseases. STATEMENT OF SIGNIFICANCE: Osteocytes are bone cells embedded in lacunae within the mineralized bone matrix and have a key role in the bone metabolism and the mineral homeostasis. Not easily accessible, we used quantitative backscattered electron imaging to determine precisely number and shape descriptors of the osteocyte lacunae in 2D. We analyzed transiliac biopsy samples from 109 individuals with age distributed from 2 to 95 years. Compact cortical bone showed constantly higher lacunar density than cancellous bone but the lacunar density in both bone tissue decreased with age before the peak bone mass age at 30 years and stabilized or even increased after this age. This extensive study provides osteocyte lacunae reference data from healthy individuals usable for bone pathology diagnosis.
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Affiliation(s)
- Stéphane Blouin
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria.
| | - Barbara M Misof
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Matthias Mähr
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Sonja Lueger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Phaedra Messmer
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Petra Keplinger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Frank Rauch
- Shriners Hospital for Children and McGill University, Montreal, ON QC, H4A 0A9, Canada
| | - Francis H Glorieux
- Shriners Hospital for Children and McGill University, Montreal, ON QC, H4A 0A9, Canada
| | - Andrea Berzlanovich
- Unit of Forensic Gerontology, Center of Forensic Medicine, Medical University of Vienna, Vienna, Austria
| | - Gerlinde M Gruber
- Department of Anatomy and Biomechanics, Karl Landsteiner University of Health Sciences, Krems, Austria
| | - Peter C Brugger
- Center for Anatomy and Cell Biology, Department of Anatomy, Medical University of Vienna, Vienna, Austria
| | - Elizabeth Shane
- Department of Medicine, Division of Endocrinology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Robert R Recker
- Osteoporosis Research Center, Creighton University, Omaha, Nebraska, USA
| | - Jochen Zwerina
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
| | - Markus A Hartmann
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria & Vienna Bone and Growth Center, Vienna, Austria
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16
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Buccino F, Aiazzi I, Casto A, Liu B, Sbarra MC, Ziarelli G, Banfi G, Vergani LM. The synergy of synchrotron imaging and convolutional neural networks towards the detection of human micro-scale bone architecture and damage. J Mech Behav Biomed Mater 2023; 137:105576. [PMID: 36413863 DOI: 10.1016/j.jmbbm.2022.105576] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 06/20/2022] [Accepted: 11/15/2022] [Indexed: 11/19/2022]
Abstract
The growing health and economic burden of bone fractures, their intricate multiscale features and the existing knowledge gaps in the comprehension of micro-scale bone damage occurrence make fracture diagnosis a challenging issue. In this scenario, deep-learning and artificial intelligence embody the new frontier of healthcare system, by overcoming the subjectivity of clinicians in the analysis of medical images. However, the preliminary attempts in exploiting the power of machine learning algorithms such as neural networks are still limited to bone macro-scale, while there is an evident lack in their application to smaller scales, where damage starts nucleating. Currently, speculations at the micro-scale are only feasible with the aid of high-resolution imaging techniques, that are particularly time consuming in terms of output images analysis. In this context, this works aims at combining the visualization of the micro-crack propagation mechanism with the promising application of convolutional neural networks. The implemented artificial intelligence tool is based for the first time on a large number of human synchrotron images coming from healthy and osteoporotic femoral heads tested under micro-compression. The designed convolutional neural networks are able to automatically detect lacunae and micro-cracks at different compression levels with high accuracy levels; indeed, with the baseline setup, networks achieve more than 0.99 level of accuracy for both cracks and lacunae, and more than 0.87 of the meanIoU adopted as validation metric. This approach is particularly encouraging for the development of powerful recognition system to comprehend bone micro-damage initiation and propagation, paving the way to the application of machine learning studies to bone micromechanics. This could be additionally crucial for future patient specific micro-scale observations to be related to the clinical practice.
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Affiliation(s)
- Federica Buccino
- Department of Mechanical Engineering, Politecnico di Milano, Italy
| | - Irene Aiazzi
- Department of Mechanical Engineering, Politecnico di Milano, Italy
| | - Alessandro Casto
- Department of Mechanical Engineering, Politecnico di Milano, Italy
| | - Bingqi Liu
- Department of Mechanical Engineering, Politecnico di Milano, Italy
| | | | - Giovanni Ziarelli
- Department of Mathematical Engineering, Politecnico di Milano, Italy
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17
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The petrous bone contains high concentrations of osteocytes: One possible reason why ancient DNA is better preserved in this bone. PLoS One 2022; 17:e0269348. [PMID: 36282813 PMCID: PMC9595551 DOI: 10.1371/journal.pone.0269348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/22/2022] [Indexed: 11/19/2022] Open
Abstract
The characterization of ancient DNA in fossil bones is providing invaluable information on the genetics of past human and other animal populations. These studies have been aided enormously by the discovery that ancient DNA is relatively well preserved in the petrous bone compared to most other bones. The reasons for this better preservation are however not well understood. Here we examine the hypothesis that one reason for better DNA preservation in the petrous bone is that fresh petrous bone contains more DNA than other bones. We therefore determined the concentrations of osteocyte cells occluded inside lacunae within the petrous bone and compared these concentrations to other bones from the domestic pig using high resolution microCT. We show that the concentrations of osteocyte lacunae in the inner layer of the pig petrous bone adjacent to the otic chamber are about three times higher (around 95,000 lacunae per mm3) than in the mastoid of the temporal bone (around 28,000 lacunae per mm3), as well as the cortical bone of the femur (around 27,000 lacunae per mm3). The sizes and shapes of the lacuna in the inner layer of the petrous bone are similar to those in the femur. We also show that the pig petrous bone lacunae do contain osteocytes using a histological stain for DNA. We therefore confirm and significantly expand upon previous observations of osteocytic lacuna concentrations in the petrous bone, supporting the notion that one possible reason for better preservation of ancient DNA in the petrous bone is that this bone initially contains at least three times more DNA than other bones. Thus during diagenesis more DNA is likely to be preserved in the petrous bone compared to other bones.
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Quantifying how altered lacunar morphology and perilacunar tissue properties influence local mechanical environment of osteocyte lacunae using finite element modeling. J Mech Behav Biomed Mater 2022; 135:105433. [DOI: 10.1016/j.jmbbm.2022.105433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/09/2022] [Accepted: 08/26/2022] [Indexed: 11/23/2022]
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Buettmann EG, Goldscheitter GM, Hoppock GA, Friedman MA, Suva LJ, Donahue HJ. Similarities Between Disuse and Age-Induced Bone Loss. J Bone Miner Res 2022; 37:1417-1434. [PMID: 35773785 PMCID: PMC9378610 DOI: 10.1002/jbmr.4643] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 06/17/2022] [Accepted: 06/24/2022] [Indexed: 11/07/2022]
Abstract
Disuse and aging are known risk factors associated with low bone mass and quality deterioration, resulting in increased fracture risk. Indeed, current and emerging evidence implicate a large number of shared skeletal manifestations between disuse and aging scenarios. This review provides a detailed overview of current preclinical models of musculoskeletal disuse and the clinical scenarios they seek to recapitulate. We also explore and summarize the major similarities between bone loss after extreme disuse and advanced aging at multiple length scales, including at the organ/tissue, cellular, and molecular level. Specifically, shared structural and material alterations of bone loss are presented between disuse and aging, including preferential loss of bone at cancellous sites, cortical thinning, and loss of bone strength due to enhanced fragility. At the cellular level bone loss is accompanied, during disuse and aging, by increased bone resorption, decreased formation, and enhanced adipogenesis due to altered gap junction intercellular communication, WNT/β-catenin and RANKL/OPG signaling. Major differences between extreme short-term disuse and aging are discussed, including anatomical specificity, differences in bone turnover rates, periosteal modeling, and the influence of subject sex and genetic variability. The examination also identifies potential shared mechanisms underlying bone loss in aging and disuse that warrant further study such as collagen cross-linking, advanced glycation end products/receptor for advanced glycation end products (AGE-RAGE) signaling, reactive oxygen species (ROS) and nuclear factor κB (NF-κB) signaling, cellular senescence, and altered lacunar-canalicular connectivity (mechanosensation). Understanding the shared structural alterations, changes in bone cell function, and molecular mechanisms common to both extreme disuse and aging are paramount to discovering therapies to combat both age-related and disuse-induced osteoporosis. © 2022 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Evan G Buettmann
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Galen M Goldscheitter
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Gabriel A Hoppock
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Michael A Friedman
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Larry J Suva
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Henry J Donahue
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
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Abusara Z, Haider I, Moo EK, Miller S, Timmermann S, Herzog W. Chondrocyte morphology as an indicator of collagen network integrity. Connect Tissue Res 2022; 63:319-328. [PMID: 34006162 DOI: 10.1080/03008207.2021.1922398] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Osteochondral allograft (OCA) transplantation offers an attractive treatment option as it can be used to repair large cartilage defects that otherwise would not heal. The currently accepted criterion for OCA selection for joint reconstruction is the percentage of viable chondrocytes, but this criterion alone may not be sufficient to ensure structural integrity and functional performance of allografts following transplantation. We sought to determine an additional parameter that indicates matrix integrity. We used multi-photon microscopy to quantitatively assess chondrocyte viability, chondrocyte shape, and collagen structure of articular cartilage of OCAs. Chondrocyte shape varied considerably in otherwise macroscopically healthy-looking OCAs with good (>90%) cell viability. Shape varied from the expected ellipsoidal form found in healthy cartilage, to excessively elongated and flattened cells that often contained multiple cytoplasmic processes reminiscent of those observed in fibroblasts. Chondrocytes with abnormal morphology were associated with degradation of their pericellular matrix and disruption of the collagen fiber orientation, reflected by an increase in heterogeneity of second harmonic signal intensity. Cell shape may be an important marker for collagen network integrity in articular cartilage in general and OCAs specifically. We propose that, aside from cell viability, cell shape may be used as an additional criterion measure for the selection of OCAs. OCAs selected for transplantation based on these criteria showed good graft-host integration post-operation. In view of the rapid and nondestructive nature of the current approach, it may be suitable for clinical application in the future.
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Affiliation(s)
- Ziad Abusara
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary.,Advanced Imaging and Histopathology Core, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Doha, Qatar
| | - Ifaz Haider
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary
| | - Eng Kuan Moo
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary.,Department of Applied Physics, University of Eastern Finland
| | - Sue Miller
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary.,Section of Orthopaedic Surgery, Department of Surgery, University of Calgary.,Taylor Institute for Teaching and Learning, University of Calgary
| | - Scott Timmermann
- McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary.,Section of Orthopaedic Surgery, Department of Surgery, University of Calgary
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary
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21
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Cui J, Shibata Y, Zhu T, Zhou J, Zhang J. Osteocytes in bone aging: Advances, challenges, and future perspectives. Ageing Res Rev 2022; 77:101608. [PMID: 35283289 DOI: 10.1016/j.arr.2022.101608] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/28/2022] [Accepted: 03/07/2022] [Indexed: 02/08/2023]
Abstract
Osteocytes play a critical role in maintaining bone homeostasis and in regulating skeletal response to hormones and mechanical loading. Substantial evidence have demonstrated that osteocytes and their lacunae exhibit morphological changes in aged bone, indicating the underlying involvement of osteocytes in bone aging. Notably, recent studies have deciphered aged osteocytes to have characteristics such as impaired mechanosensitivity, accumulated cellular senescence, dysfunctional perilacunar/canalicular remodeling, and degenerated lacuna-canalicular network. However, detailed molecular mechanisms of osteocytes remain unclear. Nonetheless, osteocyte transcriptomes analyzed via advanced RNA sequencing (RNA-seq) techniques have identified several bone aging-related genes and signaling pathways, such as Wnt, Bmp/TGF, and Jak-STAT. Moreover, inflammation, immune dysfunction, energy shortage, and impaired hormone responses possibly affect osteocytes in age-related bone deterioration. In this review, we summarize the hallmarks of aging bone and osteocytes and discuss osteocytic mechanisms in age-related bone loss and impaired bone quality. Furthermore, we provide insights into the challenges faced and their possible solutions when investigating osteocyte transcriptomes. We also highlight that single-cell RNA-seq can decode transcriptomic messages in aged osteocytes; therefore, this technique can promote novel single cell-based investigations in osteocytes once a well-established standardized protocol specific for osteocytes is developed. Interestingly, improved understanding of osteocytic mechanisms have helped identify promising targets and effective therapies for aging-related osteoporosis and fragile fractures.
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22
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Murshid SA. Bone permeability and mechanotransduction: Some current insights into the function of the lacunar-canalicular network. Tissue Cell 2022; 75:101730. [PMID: 35032785 DOI: 10.1016/j.tice.2022.101730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 10/19/2022]
Abstract
Lacunar-canalicular (LC) permeability involves the passage of fluids, nutrients, oxygen, ions, and signalling molecules through bone tissue, facilitating the maintenance of bone vitality and function and responses to various physiological conditions and diseases. LC permeability and fluid flow-shear stress/drag force play important roles in mechanotransduction in bone tissue by inducing mechanical stimuli in osteocytes, modulating cellular functions, and determining bone adaptation. Alterations in LC structure may therefore influence the fluid flow pattern through the LC network, thereby affecting the ability of osteocytes to sense and translate mechanical signals and possibly contributing to bone remodelling. Several bone-health conditions are associated with changes in LC structure and function and may affect mechanotransduction and responses, although the mechanisms underlying these associations are still not fully understood. In this review, recent studies of LC networks, their formation and transfer mechanical stimuli, and changes in structure, functional permeability, and mechanotransduction that result from age, pathology, and mechanical loading are discussed. Additionally, applications of vibration and low-intensity pulsed ultrasound in bone healthcare and regeneration fields are also presented.
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Affiliation(s)
- Sakhr Ahmed Murshid
- Institute for Globally Distributed Open Research and Education (IGDORE); Ilmajoki Health Public Dental Clinics, Social and Health Care Services in Jalasjärvi, Ilmajoki, Kurikka, Finland.
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23
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Rux CJ, Vahidi G, Darabi A, Cox LM, Heveran CM. Perilacunar bone tissue exhibits sub-micrometer modulus gradation which depends on the recency of osteocyte bone formation in both young adult and early-old-age female C57Bl/6 mice. Bone 2022; 157:116327. [PMID: 35026452 PMCID: PMC8858864 DOI: 10.1016/j.bone.2022.116327] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/19/2021] [Accepted: 01/07/2022] [Indexed: 11/18/2022]
Abstract
Osteocytes resorb and replace bone local to the lacunar-canalicular system (LCS). However, whether osteocyte remodeling impacts bone quality adjacent to the LCS is not understood. Further, while aging is well-established to decrease osteocyte viability and truncate LCS geometry, it is unclear if aging also decreases perilacunar bone quality. To address these questions, we employed atomic force microscopy (AFM) to generate nanoscale-resolution modulus maps for cortical femur osteocyte lacunae from young (5-month) and early-old-age (22-month) female C57Bl/6 mice. AFM-mapped lacunae were also imaged with confocal laser scanning microscopy to determine which osteocytes recently deposited bone as determined by the presence of fluorochrome labels administered 2d and 8d before euthanasia. Modulus gradation with distance from the lacunar wall was compared for labeled (i.e., bone forming) and non-labeled lacunae in both young and aged mice. All mapped lacunae showed sub-microscale modulus gradation, with peak modulus values 200-400 nm from the lacunar wall. Perilacunar modulus gradations depended on the recency of osteocyte bone formation (i.e., the presence of labels). For both ages, 2d-labeled perilacunar bone had lower peak and bulk modulus compared to non-labeled perilacunar bone. Lacunar length reduced with age, but lacunar shape and size were not strong predictors of modulus gradation. Our findings demonstrate for the first time that osteocyte perilacunar remodeling impacts bone tissue modulus, one contributor to bone quality. Given the immense scale of the LCS, differences in perilacunar modulus resulting from osteocyte remodeling activity may affect the quality of a substantial amount of bone tissue.
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Affiliation(s)
- Caleb J Rux
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America; UC Berkeley-UCSF Graduate Program in Bioengineering, United States of America
| | - Ghazal Vahidi
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America
| | - Amir Darabi
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America
| | - Lewis M Cox
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America
| | - Chelsea M Heveran
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America.
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24
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Sang W, Li Y, Guignon J, Liu XS, Ural A. Structural role of osteocyte lacunae on mechanical properties of bone matrix: A cohesive finite element study. J Mech Behav Biomed Mater 2022; 125:104943. [PMID: 34736032 PMCID: PMC8670554 DOI: 10.1016/j.jmbbm.2021.104943] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/05/2021] [Accepted: 10/26/2021] [Indexed: 01/03/2023]
Abstract
Despite the extensive studies on biological function of osteocytes, there are limited studies that evaluated the structural role of osteocyte lacunae on local mechanical properties of the bone matrix. As a result, the goal of this study was to elucidate the independent contribution of osteocyte lacunae structure on mechanical properties and fracture behavior of the bone matrix uncoupled from its biological effects and bone tissue composition variation. This study combined cohesive finite element modeling with experimental data from a lactation rat model to evaluate the influence of osteocyte lacunar area porosity, density, size, axis ratio, and orientation on the elastic modulus, ultimate strength, and ultimate strain of the bone matrix as well as on local crack formation and propagation. It also performed a parametric study to isolate the influence of a single osteocyte lacunae structural property on the mechanical properties of the bone matrix. The experimental measurements demonstrated statistically significant differences in lacunar size between ovariectomized rats with lactation history and virgin groups (both ovariectomized and intact) and in axis ratio between rats with lactation history and virgins. There were no differences in mechanical properties between virgin and lactation groups as determined by the finite element simulations. However, there were statistically significant linear relationships between the physiological range of osteocyte lacunar area porosity, density, size, and orientation and the elastic modulus and ultimate strength of the bone matrix in virgin and lactation rats. The parametric study also revealed similar but stronger relationships between elastic modulus and ultimate strength and lacunar density, size, and orientation. The simulations also demonstrated that the osteocyte lacunae guided the crack propagation through local stress concentrations. In summary, this study enhanced the limited knowledge on the structural role of osteocyte lacunae on local mechanical properties of the bone matrix. These data are important in gaining a better understanding of the mechanical implications of the local modifications due to osteocytes in the bone matrix.
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Affiliation(s)
- Wen Sang
- Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA, USA
| | - Yihan Li
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, 332A Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, PA, USA
| | - Jane Guignon
- Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA, USA
| | - X Sherry Liu
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, 332A Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, PA, USA
| | - Ani Ural
- Department of Mechanical Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA, USA.
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25
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Bortel E, Grover LM, Eisenstein N, Seim C, Suhonen H, Pacureanu A, Westenberger P, Raum K, Langer M, Peyrin F, Addison O, Hesse B. Interconnectivity Explains High Canalicular Network Robustness between Neighboring Osteocyte Lacunae in Human Bone. ADVANCED NANOBIOMED RESEARCH 2021. [DOI: 10.1002/anbr.202100090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Emely Bortel
- Xploraytion GmbH Bismarckstrasse 10-12 10625 Berlin Germany
| | - Liam M Grover
- School of Chemical Engineering University of Birmingham B15 2TT Birmingham UK
| | - Neil Eisenstein
- School of Chemical Engineering University of Birmingham B15 2TT Birmingham UK
| | - Christian Seim
- Xploraytion GmbH Bismarckstrasse 10-12 10625 Berlin Germany
- Technical University of Berlin: Institute of Optics and Atomic Physics 10623 Berlin Germany
| | - Heikki Suhonen
- University of Helsinki: Department of Physics 00560 Helsinki Finland
| | | | | | - Kay Raum
- Charité—Universitätsmedizin Berlin Corporate Member of Freie Universität Berlin Humboldt-Universität zu Berlinand Berlin Institute of Health BCRT—Berlin Institute of Health Center for Regenerative Therapies 13353 Berlin Germany
| | - Max Langer
- Univ Lyon CNRS 5220Inserm U1294INSA Lyon 69621 Creatis Villeurbanne Cedex France
- Université Grenoble Alpes CNRSUMR 5525 VetAgro SupGrenoble INPTIMC F-38000 Grenoble France
| | - Francoise Peyrin
- ESRF: Experiment Division 38000 Grenoble France
- Univ Lyon CNRS 5220Inserm U1294INSA Lyon 69621 Creatis Villeurbanne Cedex France
| | - Owen Addison
- Faculty of Dentistry Oral and Craniofacial Sciences Kings College SE1 9RT London UK
| | - Bernhard Hesse
- Xploraytion GmbH Bismarckstrasse 10-12 10625 Berlin Germany
- ESRF: Experiment Division 38000 Grenoble France
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26
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Dixit M, Duran‐Ortiz S, Yildirim G, Poudel SB, Louis LD, Bartke A, Schaffler MB, Kopchick JJ, Yakar S. Induction of somatopause in adult mice compromises bone morphology and exacerbates bone loss during aging. Aging Cell 2021; 20:e13505. [PMID: 34811875 PMCID: PMC8672783 DOI: 10.1111/acel.13505] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/31/2021] [Accepted: 09/29/2021] [Indexed: 12/23/2022] Open
Abstract
Somatopause refers to the gradual declines in growth hormone (GH) and insulin‐like growth factor‐1 throughout aging. To define how induced somatopause affects skeletal integrity, we used an inducible GH receptor knockout (iGHRKO) mouse model. Somatopause, induced globally at 6 months of age, resulted in significantly more slender bones in both male and female iGHRKO mice. In males, induced somatopause was associated with progressive expansion of the marrow cavity leading to significant thinning of the cortices, which compromised bone strength. We report progressive declines in osteocyte lacunar number, and increases in lacunar volume, in iGHRKO males, and reductions in lacunar number accompanied by ~20% loss of overall canalicular connectivity in iGHRKO females by 30 months of age. Induced somatopause did not affect mineral/matrix ratio assessed by Raman microspectroscopy. We found significant increases in bone marrow adiposity and high levels of sclerostin, a negative regulator of bone formation in iGHRKO mice. Surprisingly, however, despite compromised bone morphology, osteocyte senescence was reduced in the iGHRKO mice. In this study, we avoided the confounded effects of constitutive deficiency in the GH/IGF‐1 axis on the skeleton during growth, and specifically dissected its effects on the aging skeleton. We show here, for the first time, that induced somatopause compromises bone morphology and the bone marrow environment.
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Affiliation(s)
- Manisha Dixit
- David B. Kriser Dental Center Department of Molecular Pathobiology New York University College of Dentistry New York New York NY USA
| | - Silvana Duran‐Ortiz
- Edison Biotechnology Institute and Dept. of Biomedical Sciences Ohio University Athens OH USA
| | - Godze Yildirim
- David B. Kriser Dental Center Department of Molecular Pathobiology New York University College of Dentistry New York New York NY USA
| | - Sher Bahadur Poudel
- David B. Kriser Dental Center Department of Molecular Pathobiology New York University College of Dentistry New York New York NY USA
| | - Leeann D. Louis
- Department of Biomedical Engineering City College of New York New York NY USA
| | - Andrzej Bartke
- Southern Illinois University School of Medicine Springfield IL USA
| | | | - John J. Kopchick
- Edison Biotechnology Institute and Dept. of Biomedical Sciences Ohio University Athens OH USA
| | - Shoshana Yakar
- David B. Kriser Dental Center Department of Molecular Pathobiology New York University College of Dentistry New York New York NY USA
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27
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Hemmatian H, Bakker AD, Klein-Nulend J, van Lenthe GH. Alterations in osteocyte lacunar morphology affect local bone tissue strains. J Mech Behav Biomed Mater 2021; 123:104730. [PMID: 34438250 DOI: 10.1016/j.jmbbm.2021.104730] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/16/2021] [Accepted: 07/17/2021] [Indexed: 11/17/2022]
Abstract
Osteocytes are capable of remodeling their perilacunar bone matrix, which causes considerable variations in the shape and size of their lacunae. If these variations in lacunar morphology cause changes in the mechanical environment of the osteocytes, in particular local strains, they would subsequently affect bone mechanotransduction, since osteocytes are likely able to directly sense these strains. The purpose of this study is to quantify the effect of alterations in osteocyte lacunar morphology on peri-lacunar bone tissue strains. To this end, we related the actual lacunar shape in fibulae of six young-adult (5-month) and six old (23-month) mice, quantified by high-resolution micro-computed tomography, to microscopic strains, analyzed by micro-finite element modeling. We showed that peak effective strain increased by 12.6% in osteocyte cell bodies (OCYs), 9.6% in pericellular matrix (PCM), and 5.3% in extra cellular matrix (ECM) as the lacunae volume increased from 100-200 μm3 to 500-600 μm3. Lacunae with a larger deviation (>8°) in orientation from the longitudinal axis of the bone are exposed to 8% higher strains in OCYs, 6.5% in PCM, 4.2% in ECM than lacunae with a deviation in orientation below 8°. Moreover, increased lacuna sphericity from 0 to 0.5 to 0.7-1 led to 25%, 23%, and 13% decrease in maximum effective strains in OCYs, PCM, and ECM, respectively. We further showed that due to the presence of smaller and more round lacunae in old mice, local bone tissue strains are on average 5% lower in the vicinity of lacunae and their osteocytes of old mice compared to young. Understanding how changes in lacunar morphology affect the micromechanical environment of osteocytes presents a first step in unraveling their potential role in impaired bone mechanoresponsiveness with e.g. aging.
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Affiliation(s)
- Haniyeh Hemmatian
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium; Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands; Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Astrid D Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - G Harry van Lenthe
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
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28
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Jähn-Rickert K, Zimmermann EA. Potential Role of Perilacunar Remodeling in the Progression of Osteoporosis and Implications on Age-Related Decline in Fracture Resistance of Bone. Curr Osteoporos Rep 2021; 19:391-402. [PMID: 34117624 DOI: 10.1007/s11914-021-00686-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/22/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW We took an interdisciplinary view to examine the potential contribution of perilacunar/canalicular remodeling to declines in bone fracture resistance related to age or progression of osteoporosis. RECENT FINDINGS Perilacunar remodeling is most prominent as a result of lactation; recent advances further elucidate the molecular players involved and their effect on bone material properties. Of these, vitamin D and calcitonin could be active during aging or osteoporosis. Menopause-related hormonal changes or osteoporosis therapies affect bone material properties and mechanical behavior. However, investigations of lacunar size or osteocyte TRAP activity with age or osteoporosis do not provide clear evidence for or against perilacunar remodeling. While the occurrence and potential role of perilacunar remodeling in aging and osteoporosis progression are largely under-investigated, widespread changes in bone matrix composition in OVX models and following osteoporosis therapies imply osteocytic maintenance of bone matrix. Perilacunar remodeling-induced changes in bone porosity, bone matrix composition, and bone adaptation could have significant implications for bone fracture resistance.
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Affiliation(s)
- Katharina Jähn-Rickert
- Heisenberg Research Group, Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 55a, 22529, Hamburg, Germany.
- Mildred Scheel Cancer Career Center Hamburg, University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Elizabeth A Zimmermann
- Faculty of Dentistry, McGill University, Strathcona Anatomy and Dentistry Building, 3640 Rue University, Montreal, Canada.
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29
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Chang B, Liu X. Osteon: Structure, Turnover, and Regeneration. TISSUE ENGINEERING PART B-REVIEWS 2021; 28:261-278. [PMID: 33487116 DOI: 10.1089/ten.teb.2020.0322] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Bone is composed of dense and solid cortical bone and honeycomb-like trabecular bone. Although cortical bone provides the majority of mechanical strength for a bone, there are few studies focusing on cortical bone repair or regeneration. Osteons (the Haversian system) form structural and functional units of cortical bone. In recent years, emerging evidences have shown that the osteon structure (including osteocytes, lamellae, lacunocanalicular network, and Haversian canals) plays critical roles in bone mechanics and turnover. Therefore, reconstruction of the osteon structure is crucial for cortical bone regeneration. This article provides a systematic summary of recent advances in osteons, including the structure, function, turnover, and regenerative strategies. First, the hierarchical structure of osteons is illustrated and the critical functions of osteons in bone dynamics are introduced. Next, the modeling and remodeling processes of osteons at a cellular level and the turnover of osteons in response to mechanical loading and aging are emphasized. Furthermore, several bioengineering approaches that were recently developed to recapitulate the osteon structure are highlighted. Impact statement This review provides a comprehensive summary of recent advances in osteons, especially the roles in bone formation, remodeling, and regeneration. Besides introducing the hierarchical structure and critical functions of osteons, we elucidate the modeling and remodeling of osteons at a cellular level. Specifically, we highlight the bioengineering approaches that were recently developed to mimic the hierarchical structure of osteons. We expect that this review will provide informative insights and attract increasing attentions in orthopedic community, shedding light on cortical bone regeneration in the future.
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Affiliation(s)
- Bei Chang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, Texas, USA
| | - Xiaohua Liu
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, Texas, USA
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30
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Vahidi G, Rux C, Sherk VD, Heveran CM. Lacunar-canalicular bone remodeling: Impacts on bone quality and tools for assessment. Bone 2021; 143:115663. [PMID: 32987198 PMCID: PMC7769905 DOI: 10.1016/j.bone.2020.115663] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/23/2020] [Accepted: 09/23/2020] [Indexed: 01/06/2023]
Abstract
Osteocytes can resorb as well as replace bone adjacent to the expansive lacunar-canalicular system (LCS). Suppressed LCS remodeling decreases bone fracture toughness, but it is unclear how altered LCS remodeling impacts bone quality. The first goal of this review is to assess how LCS remodeling impacts LCS morphology as well as the composition and mechanical properties of surrounding bone tissue. The second goal is to compare tools available for the assessment of bone quality at length-scales that are physiologically-relevant to LCS remodeling. We find that changes to LCS morphology occur in response to a variety of physiological conditions and diseases and can be classified in two general phenotypes. In the 'aging phenotype', seen in aging and in some disuse models, the LCS is truncated and osteocytes apoptosis is increased. In the 'osteocytic osteolysis' phenotype, which is adaptive in some physiological settings and possibly maladaptive in others, the LCS enlarges and osteocytes generally maintain viability. Bone composition and mechanical properties vary near the osteocyte and change with at least some conditions that alter LCS morphology. However, few studies have evaluated bone composition and mechanical properties close to the LCS and so the impacts of LCS remodeling phenotypes on bone tissue quality are still undetermined. We summarize the current understanding of how LCS remodeling impacts LCS morphology, tissue-scale bone composition and mechanical properties, and whole-bone material properties. Tools are compared for assessing tissue-scale bone properties, as well as the resolution, advantages, and limitations of these techniques.
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Affiliation(s)
- G Vahidi
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America
| | - C Rux
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America
| | - V D Sherk
- Department of Orthopedics, University of Colorado Anschutz School of Medicine, United States of America
| | - C M Heveran
- Department of Mechanical & Industrial Engineering, Montana State University, United States of America.
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31
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Akhter MP, Recker RR. High resolution imaging in bone tissue research-review. Bone 2021; 143:115620. [PMID: 32866682 DOI: 10.1016/j.bone.2020.115620] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 12/14/2022]
Abstract
This review article focuses on imaging of bone tissue to understand skeletal health with regards to bone quality. Skeletal fragility fractures are due to bone diseases such as osteoporosis which result in low bone mass and bone mineral density (BMD) leading to high risk of fragility fractures. Recent advances in imaging and analysis technologies have highly benefitted the field of biological sciences. In particular, their application in skeletal health has been of significant importance in understanding bone mechanical behavior (structure and properties) at the tissue level. While synchrotron based microCT technique has remained the gold standard for non-destructive evaluation of structure in material and biological sciences, several lab based microCT systems have been developed to provide high resolution imaging of specimens with greater access, and ease of use in laboratory settings. Lab based microCT scanners are widely used in the bone field as a standard tool to evaluate three-dimensional (3D) morphologies of bone structure at image resolutions appropriate for bone samples from small animals to bone biopsy specimens from humans. Both synchrotron and standard lab based microCT systems provide high resolution imaging ex vivo for a small sized specimen. A few X-ray based systems are also commercially available for in vivo scanning at relatively low image resolutions. Synchrotron-based CT microscopy is being used for various ultra-high-resolution image analyses using complex 3D software. However, the synchrotron-based CT technology is in high demand, allows only limited numbers of specimens, expensive, requires complex additional instrumentation, and is not easily available to researchers as it requires access to a synchrotron source which is always limited. Therefore, desktop laboratory scanners (microXCT, Zeiss/Xradia, Scanco, SkyScan. etc.), mimicking the synchrotron based CT technology or image resolution, have been developed to solve the accessibility issues. These lab based scanners have helped both material science, and the bone field to investigate bone tissue morphologies at submicron mage resolutions. Considerable progress has been made in both in vivo and ex vivo imaging towards providing high resolution images of bone tissue. Both clinical and research imaging technologies will continue to improve and help understand osteoporosis and other related skeletal issues in order to develop targeted treatments for bone fragility. This review summarizes the high resolution imaging work in bone research.
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Affiliation(s)
- M P Akhter
- Creighton University Osteoporosis Research Center, Omaha, NE, United States of America.
| | - R R Recker
- Creighton University Osteoporosis Research Center, Omaha, NE, United States of America
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Maggiano IS, Maggiano CM, Cooper DML. Osteon circularity and longitudinal morphology: Quantitative and qualitative three-dimensional perspectives on human Haversian systems. Micron 2021; 140:102955. [DOI: 10.1016/j.micron.2020.102955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/14/2020] [Accepted: 09/29/2020] [Indexed: 11/30/2022]
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Yu B, Pacureanu A, Olivier C, Cloetens P, Peyrin F. Quantification of the bone lacunocanalicular network from 3D X-ray phase nanotomography images. J Microsc 2020; 282:30-44. [PMID: 33125757 DOI: 10.1111/jmi.12973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 10/07/2020] [Accepted: 10/18/2020] [Indexed: 11/30/2022]
Abstract
There is a growing interest in developing 3D microscopy for the exploration of thick biological tissues. Recently, 3D X-ray nanocomputerised tomography has proven to be a suitable technique for imaging the bone lacunocanalicular network. This interconnected structure is hosting the osteocytes which play a major role in maintaining bone quality through remodelling processes. 3D images have the potential to reveal the architecture of cellular networks, but their quantitative analysis remains a challenge due to the density and complexity of nanometre sized structures and the need to handle and process large datasets, for example, 20483 voxels corresponding to 32 GB per individual image in our case. In this work, we propose an efficient image processing approach for the segmentation of the network and the extraction of characteristic parameters describing the 3D structure. These parameters include the density of lacunae, the porosity of lacunae and canaliculi, and morphological features of lacunae (volume, surface area, lengths, anisotropy etc.). We also introduce additional parameters describing the local environment of each lacuna and its canaliculi. The method is applied to analyse eight human femoral cortical bone samples imaged by magnified X-ray phase nanotomography with a voxel size of 120 nm, which was found to be a good compromise to resolve canaliculi while keeping a sufficiently large field of view of 246 μm in 3D. The analysis was performed on a total of 2077 lacunae showing an average length, width and depth of 17.1 μm × 9.2 μm × 4.4 μm, with an average number of 58.2 canaliculi per lacuna and a total lacuno-canalicular porosity of 1.12%. The reported descriptive parameters provide information on the 3D organisation of the lacuno-canalicular network in human bones.
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Affiliation(s)
- Boliang Yu
- Univ Lyon, CNRS, INSERM, INSA Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CREATIS, UMR 5220, U1206, Lyon, France
| | - Alexandra Pacureanu
- Univ Lyon, CNRS, INSERM, INSA Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CREATIS, UMR 5220, U1206, Lyon, France
| | - Cecile Olivier
- Univ Lyon, CNRS, INSERM, INSA Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CREATIS, UMR 5220, U1206, Lyon, France.,ESRF, the European Synchrotron, Grenoble, France
| | | | - Francoise Peyrin
- Univ Lyon, CNRS, INSERM, INSA Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CREATIS, UMR 5220, U1206, Lyon, France.,ESRF, the European Synchrotron, Grenoble, France
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Williams KA, Gostling NJ, Steer JW, Oreffo ROC, Schneider P. Quantifying intracortical bone microstructure: A critical appraisal of 2D and 3D approaches for assessing vascular canals and osteocyte lacunae. J Anat 2020; 238:653-668. [PMID: 33090473 PMCID: PMC7855084 DOI: 10.1111/joa.13325] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 09/04/2020] [Accepted: 09/10/2020] [Indexed: 02/04/2023] Open
Abstract
Describing and quantifying vascular canal orientation and volume of osteocyte lacunae in bone is important in studies of bone growth, mechanics, health and disease. It is also an important element in analysing fossil bone in palaeohistology, key to understanding the growth, life and death of extinct animals. Often, bone microstructure is studied using two-dimensional (2D) sections, and three-dimensional (3D) shape and orientation of structures are estimated by modelling the structures using idealised geometries based on information from their cross sections. However, these methods rely on structures meeting strict geometric assumptions. Recently, 3D methods have been proposed which could provide a more accurate and robust approach to bone histology, but these have not been tested in direct comparison with their 2D counterparts in terms of accuracy and sensitivity to deviations from model assumptions. We compared 2D and 3D methodologies for estimating key microstructural traits using a combination of experimental and idealised test data sets. We generated populations of cylinders (canals) and ellipsoids (osteocyte lacunae), varying the cross-sectional aspect ratios of cylinders and orientation of ellipsoids to test sensitivity to deviations from cylindricality and longitudinal orientation, respectively. Using published methods, based on 2D sections and 3D data sets, we estimated cylinder orientation and ellipsoid volume. We applied the same methods to six CT data sets of duck cortical bone, using the full volumes for 3D measurements and single CT slices to represent 2D sections. Using in silico test data sets that did deviate from ideal cylinders and ellipsoids resulted in inaccurate estimates of cylinder or canal orientation, and reduced accuracy in estimates of ellipsoid and lacunar volume. These results highlight the importance of using appropriate 3D imaging and quantitative methods for quantifying volume and orientation of 3D structures and offer approaches to significantly enhance our understanding of bone physiology based on accurate measures for bone microstructures.
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Affiliation(s)
- Katherine A. Williams
- Bioengineering Science Research GroupFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUnited Kingdom
| | - Neil J. Gostling
- School of Biological SciencesFaculty of Environmental and Biological SciencesUniversity of SouthamptonSouthamptonUnited Kingdom
| | - Joshua W. Steer
- Bioengineering Science Research GroupFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUnited Kingdom
| | - Richard O. C. Oreffo
- Bone and Joint Research GroupCentre for Human DevelopmentStem Cells and RegenerationInstitute of Developmental SciencesFaculty of MedicineUniversity of SouthamptonSouthamptonUnited Kingdom
| | - Philipp Schneider
- Bioengineering Science Research GroupFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthamptonUnited Kingdom
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35
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Assessment of the human bone lacuno-canalicular network at the nanoscale and impact of spatial resolution. Sci Rep 2020; 10:4567. [PMID: 32165649 PMCID: PMC7067834 DOI: 10.1038/s41598-020-61269-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 02/17/2020] [Indexed: 11/09/2022] Open
Abstract
Recently, increasing attention has been given to the study of osteocytes, the cells that are thought to play an important role in bone remodeling and in the mechanisms of bone fragility. The interconnected osteocyte system is deeply embedded inside the mineralized bone matrix and lies within a closely fitted porosity known as the lacuno-canalicular network. However, quantitative data on human samples remain scarce, mostly measured in 2D, and there are gaps to be filled in terms of spatial resolution. In this work, we present data on femoral samples from female donors imaged with isotropic 3D spatial resolution by magnified X-ray phase nano computerized-tomography. We report quantitative results on the 3D structure of canaliculi in human femoral bone imaged with a voxel size of 30 nm. We found that the lacuno-canalicular porosity occupies on average 1.45% of the total tissue volume, the ratio of the canalicular versus lacunar porosity is about 37.7%, and the primary number of canaliculi stemming from each lacuna is 79 on average. The examination of this number at different distances from the surface of the lacunae demonstrates branching in the canaliculi network. We analyzed the impact of spatial resolution on quantification by comparing parameters extracted from the same samples imaged with 120 nm and 30 nm voxel sizes. To avoid any bias related to the analysis region, the volumes at 120 nm and 30 nm were registered and cropped to the same field of view. Our results show that the measurements at 120 and 30 nm are strongly correlated in our data set but that the highest spatial resolution provides more accurate information on the canaliculi network and its branching properties.
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Iezzi G, Mangano C, Barone A, Tirone F, Baggi L, Tromba G, Piattelli A, Giuliani A. Jawbone remodeling: a conceptual study based on Synchrotron High-resolution Tomography. Sci Rep 2020; 10:3777. [PMID: 32123216 PMCID: PMC7052147 DOI: 10.1038/s41598-020-60718-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/10/2020] [Indexed: 12/13/2022] Open
Abstract
One of the most important aspects of bone remodeling is the constant turnover mainly driven by the mechanical loading stimulus. The remodeling process produces changes not only in the bone microarchitecture but also in the density distribution of the mineralized matrix - i.e. in calcium concentrations- and in the osteocyte lacunar network. Synchrotron radiation-based X-ray microtomography (microCT) has proven to be an efficient technique, capable to achieve the analysis of 3D bone architecture and of local mineralization at different hierarchical length scales, including the imaging of the lacuno-canalicular network. In the present study, we used microCT within a conceptual study of jawbone remodeling, demonstratively focusing the investigation in two critical contexts, namely in the peri-dental and the peri-implant tissues. The microCT analysis showed that a relevant inhomogeneity was clearly present in both peri-dental and peri-implant biopsies, not only in terms of microarchitecture and mineralization degree, but also considering the lacunar network, i.e. size and numerical density of the osteocyte lacunae. The correlated histological results obtained on the same samples confirmed these observations, also adding information related to non-mineralized tissues. Despite its demonstrative nature, it was concluded that the proposed method was powerful in studying jawbone remodeling because it revealed a direct correlation of its rate with the lacunar density, as achieved by the analysis of the osteocyte lacunar network, and an inverse correlation with the local bone mineral density, as revealed with the Roschger approach.
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Affiliation(s)
- Giovanna Iezzi
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti Scalo, CH, Italy
| | | | - Antonio Barone
- Department of Medical, Surgical, Molecular and of the Critical Area Pathologies, University of Pisa, Pisa, Italy
| | | | - Luigi Baggi
- Department of Social Dentistry, National Institute for Health, Migration and Poverty, Rome, Italy.,School of Dentistry, University of Rome "Tor Vergata", Rome, Italy
| | | | - Adriano Piattelli
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti Scalo, CH, Italy.,Chair of Biomaterials Engineering, Catholic University of Murcia (UCAM), Murcia, Spain.,Villa Serena Foundation for Research, Città Sant'Angelo (Pescara), Italy
| | - Alessandra Giuliani
- Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
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37
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van Tol AF, Roschger A, Repp F, Chen J, Roschger P, Berzlanovich A, Gruber GM, Fratzl P, Weinkamer R. Network architecture strongly influences the fluid flow pattern through the lacunocanalicular network in human osteons. Biomech Model Mechanobiol 2019; 19:823-840. [PMID: 31782029 PMCID: PMC7203595 DOI: 10.1007/s10237-019-01250-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 11/04/2019] [Indexed: 12/24/2022]
Abstract
A popular hypothesis explains the mechanosensitivity of bone due to osteocytes sensing the load-induced flow of interstitial fluid squeezed through the lacunocanalicular network (LCN). However, the way in which the intricate structure of the LCN influences fluid flow through the network is largely unexplored. We therefore aimed to quantify fluid flow through real LCNs from human osteons using a combination of experimental and computational techniques. Bone samples were stained with rhodamine to image the LCN with 3D confocal microscopy. Image analysis was then performed to convert image stacks into mathematical network structures, in order to estimate the intrinsic permeability of the osteons as well as the load-induced fluid flow using hydraulic circuit theory. Fluid flow was studied in both ordinary osteons with a rather homogeneous LCN as well as a frequent subtype of osteons-so-called osteon-in-osteons-which are characterized by a ring-like zone of low network connectivity between the inner and the outer parts of these osteons. We analyzed 8 ordinary osteons and 9 osteon-in-osteons from the femur midshaft of a 57-year-old woman without any known disease. While the intrinsic permeability was 2.7 times smaller in osteon-in-osteons compared to ordinary osteons, the load-induced fluid velocity was 2.3 times higher. This increased fluid velocity in osteon-in-osteons can be explained by the longer path length, needed to cross the osteon from the cement line to the Haversian canal, including more fluid-filled lacunae and canaliculi. This explanation was corroborated by the observation that a purely structural parameter-the mean path length to the Haversian canal-is an excellent predictor for the average fluid flow velocity. We conclude that osteon-in-osteons may be particularly significant contributors to the mechanosensitivity of cortical bone, due to the higher fluid flow in this type of osteons.
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Affiliation(s)
- Alexander F van Tol
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany. .,Berlin-Brandenburg School of Regenerative Therapies (BSRT), Föhrer Str. 15, 13353, Berlin, Germany.
| | - A Roschger
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.,Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Jakrob-Haringer Straße 2a, 5020, Salzburg, Austria
| | - F Repp
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
| | - J Chen
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.,College of Engineering, Mathematics, and Physical Science, University of Exeter, Exeter, EX4 4QF, UK
| | - P Roschger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Heinrich Collin Str. 30, 1140, Vienna, Austria
| | - A Berzlanovich
- Center of Forensic Science, Medical University of Vienna, Sensengasse 2, 1090, Vienna, Austria
| | - G M Gruber
- Department of Anatomy, Center for Anatomy and Cell Biology, Medical University of Vienna, 1090, Vienna, Austria
| | - P Fratzl
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
| | - Richard Weinkamer
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
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38
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Abstract
PURPOSE OF REVIEW In perilacunar/canalicular remodeling (PLR), osteocytes dynamically resorb, and then replace, the organic and mineral components of the pericellular extracellular matrix. Given the enormous surface area of the osteocyte lacuna-canalicular network (LCN), PLR is important for maintaining homeostasis of the skeleton. The goal of this review is to examine the motivations and critical considerations for the analysis of PLR, in both in vitro and in vivo systems. RECENT FINDINGS Morphological approaches alone are insufficient to elucidate the complex mechanisms regulating PLR in the healthy skeleton and in disease. Understanding the role and regulation of PLR will require the incorporation of standardized PLR outcomes as a routine part of skeletal phenotyping, as well as the development of improved molecular and cellular outcomes. Current PLR outcomes assess PLR enzyme expression, the LCN, and bone matrix composition and organization, among others. Here, we discuss current PLR outcomes and how they have been applied to study PLR induction and suppression in vitro and in vivo. Given the role of PLR in skeletal health and disease, integrated analysis of PLR has potential to elucidate new mechanisms by which osteocytes participate in skeletal health and disease.
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Affiliation(s)
- Cristal S Yee
- Department of Orthopaedic Surgery, University of California, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
| | - Charles A Schurman
- Department of Orthopaedic Surgery, University of California, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
- UC Berkeley/UCSF Graduate Program in Bioengineering, San Francisco, CA, 94143, USA
| | - Carter R White
- Department of Orthopaedic Surgery, University of California, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
| | - Tamara Alliston
- Department of Orthopaedic Surgery, University of California, 513 Parnassus Avenue, San Francisco, CA, 94143, USA.
- UC Berkeley/UCSF Graduate Program in Bioengineering, San Francisco, CA, 94143, USA.
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39
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Tiede-Lewis LM, Dallas SL. Changes in the osteocyte lacunocanalicular network with aging. Bone 2019; 122:101-113. [PMID: 30743014 PMCID: PMC6638547 DOI: 10.1016/j.bone.2019.01.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 01/28/2019] [Indexed: 12/22/2022]
Abstract
Osteoporosis is an aging-related disease of reduced bone mass that is particularly prevalent in post-menopausal women, but also affects the aged male population and is associated with increased fracture risk. Osteoporosis is the result of an imbalance whereby bone formation by osteoblasts no longer keeps pace with resorption of bone by osteoclasts. Osteocytes are the most abundant cells in bone and, although previously thought to be quiescent, they are now known to be active, multifunctional cells that play a key role in the maintenance of bone mass by regulating both osteoblast and osteoclast activity. They are also thought to regulate bone mass through their role as mechanoresponsive cells in bone that coordinate adaptive responses to mechanical loading. Osteocytes form an extensive interconnected network throughout the mineralized bone matrix and receive their nutrients as well as hormones and signaling factors through the lacunocanalicular system. Several studies have shown that the extent and connectivity of the lacunocanalicular system and osteocyte networks degenerates in aged humans as well as in animal models of aging. It is also known that the bone anabolic response to loading is decreased with aging. This review summarizes recent research on the degenerative changes that occur in osteocytes and their lacunocanalicular system as a result of aging and discusses the implications for skeletal health and homeostasis as well as potential mechanisms that may underlie these degenerative changes. Since osteocytes are such key regulators of skeletal homeostasis, maintaining the health of the osteocyte network would seem critical for maintenance of bone health. Therefore, a more complete understanding of the structure and function of the osteocyte network, its lacunocanalicular system, and the degenerative changes that occur with aging should lead to advances in our understanding of age related bone loss and potentially lead to improved therapies.
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Affiliation(s)
- LeAnn M Tiede-Lewis
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO 64108, United States of America
| | - Sarah L Dallas
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO 64108, United States of America.
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40
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Beresheim AC, Pfeiffer SK, Grynpas MD, Alblas A. Use of backscattered scanning electron microscopy to quantify the bone tissues of mid‐thoracic human ribs. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 168:262-278. [DOI: 10.1002/ajpa.23716] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 09/10/2018] [Accepted: 09/11/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Amy C. Beresheim
- Department of AnthropologyUniversity of Toronto Toronto Ontario Canada
| | - Susan K. Pfeiffer
- Department of AnthropologyUniversity of Toronto Toronto Ontario Canada
- Department of ArchaeologyUniversity of Cape Town Rondebosch Cape Town South Africa
- Department of Anthropology and Center for Advanced Study of Human PaleobiologyGeorge Washington University Washington, D.C
| | - Marc D. Grynpas
- Department of Laboratory Medicine and Pathobiology and Institute for Biomaterials and Biomedical EngineeringUniversity of Toronto Toronto Ontario Canada
- Lunenfeld‐Tanenbaum Research Institute, Mount Sinai Hospital Toronto Ontario Canada
| | - Amanda Alblas
- Division of Anatomy and Histology, Department of Biomedical SciencesStellenbosch University Cape Town South Africa
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41
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Hemmatian H, Jalali R, Semeins CM, Hogervorst JMA, van Lenthe GH, Klein-Nulend J, Bakker AD. Mechanical Loading Differentially Affects Osteocytes in Fibulae from Lactating Mice Compared to Osteocytes in Virgin Mice: Possible Role for Lacuna Size. Calcif Tissue Int 2018; 103:675-685. [PMID: 30109376 PMCID: PMC6208961 DOI: 10.1007/s00223-018-0463-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/30/2018] [Indexed: 12/31/2022]
Abstract
Hormonal changes during lactation are associated with profound changes in bone cell biology, such as osteocytic osteolysis, resulting in larger lacunae. Larger lacuna shape theoretically enhances the transmission of mechanical signals to osteocytes. We aimed to provide experimental evidence supporting this theory by comparing the mechanoresponse of osteocytes in the bone of lactating mice, which have enlarged lacunae due to osteocytic osteolysis, with the response of osteocytes in bone from age-matched virgin mice. The osteocyte mechanoresponse was measured in excised fibulae that were cultured in hormone-free medium for 24 h and cyclically loaded for 10 min (sinusoidal compressive load, 3000 µε, 5 Hz) by quantifying loading-related changes in Sost mRNA expression (qPCR) and sclerostin and β-catenin protein expression (immunohistochemistry). Loading decreased Sost expression by ~ threefold in fibulae of lactating mice. The loading-induced decrease in sclerostin protein expression by osteocytes was larger in lactating mice (55% decrease ± 14 (± SD), n = 8) than virgin mice (33% decrease ± 15, n = 7). Mechanical loading upregulated β-catenin expression in osteocytes in lactating mice by 3.5-fold (± 0.2, n = 6) which is significantly (p < 0.01) higher than the 1.6-fold increase in β-catenin expression by osteocytes in fibulae from virgin mice (± 0.12, n = 4). These results suggest that osteocytes in fibulae from lactating mice with large lacunae may respond stronger to mechanical loading than those from virgin mice. This could indicate that osteocytes residing in larger lacuna show a stronger response to mechanical loading.
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Affiliation(s)
- Haniyeh Hemmatian
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands
| | - Rozita Jalali
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands
| | - Cornelis M Semeins
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands
| | - Jolanda M A Hogervorst
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands
| | - G Harry van Lenthe
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
| | - Astrid D Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands
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42
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Andronowski JM, Crowder C, Soto Martinez M. Recent advancements in the analysis of bone microstructure: New dimensions in forensic anthropology. Forensic Sci Res 2018; 3:278-293. [PMID: 30788447 PMCID: PMC6374927 DOI: 10.1080/20961790.2018.1483294] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 05/30/2018] [Indexed: 10/29/2022] Open
Abstract
Bone is a mechanically active, three-dimensionally (3D) complex, and dynamic tissue that changes in structure over the human lifespan. Bone tissue exists and remodels in 3D and changes over time, introducing a fourth dimension. The products of the remodelling process, secondary and fragmentary osteons, have been studied substantially using traditional two-dimensional (2D) techniques. As a result, much has been learned regarding the biological information encrypted in the histomorphology of bone, yielding a wealth of information relating to skeletal structure and function. Three-dimensional imaging modalities, however, hold the potential to provide a much more comprehensive understanding of bone microarchitecture. The visualization and analysis of bone using high-resolution 3D imaging will improve current understandings of bone biology and have numerous applications in both biological anthropology and biomedicine. Through recent technological advancements, we can hone current anthropological applications of the analysis of bone microstructure and accelerate research into the third and fourth dimensional realms. This review will explore the methodological approaches used historically by anthropologists to assess cortical bone microstructure, spanning from histology to current ex vivo imaging modalities, discuss the growing capabilities of in vivo imaging, and conclude with an introduction of novel non-histological modalities for investigating bone quality.
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43
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Hemmatian H, Laurent MR, Bakker AD, Vanderschueren D, Klein-Nulend J, van Lenthe GH. Age-related changes in female mouse cortical bone microporosity. Bone 2018; 113:1-8. [PMID: 29738854 DOI: 10.1016/j.bone.2018.05.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 04/04/2018] [Accepted: 05/02/2018] [Indexed: 12/23/2022]
Abstract
Osteocyte lacunae are small cavities within the bone matrix. Their dimensions and spatial arrangement affect bone mechanical properties. Furthermore, their size and shape affect the strain in bone tissue close to the lacunae; hence, they are supposed to affect the mechanosensory function of the osteocytes residing in the lacunae. It was the purpose of this study to quantify the morphological features of osteocyte lacunae, whether these are affected by aging and whether these vary among different anatomical location. In addition, we aimed at quantifying the vascular canals as these affect bone's microporosity too. We quantified the microporosity in the fibular midshaft of young-adult and old female C57BL/6 mice. Using micro-computed tomography (μCT), we found that advanced age was associated with a significantly decreased vascular canal number and volume density. In aged mice, the mean volume of the lacuna was significantly smaller than in young animals and they were more round. Lacuna number density close to the neutral axis of the fibula was higher in older mice than in young ones. The characterization of bone microporosity presents a first step in further unraveling their potential role in age-related reductions in bone strength.
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Affiliation(s)
- Haniyeh Hemmatian
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium; Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Michaël R Laurent
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium; Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Astrid D Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Dirk Vanderschueren
- Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - G Harry van Lenthe
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
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44
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Stigler RG, Becker K, Kloss FR, Gassner R, Lepperdinger G. Long-lived murine osteocytes are embodied by craniofacial skeleton in young and old animals whereas they decrease in number in postcranial skeletons at older ages. Gerodontology 2018; 35:391-397. [PMID: 30052290 DOI: 10.1111/ger.12362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Osteocytes are engaged in life-enduring processes such as bone remodelling, fracture healing or osseointegration of implants. Over age, ossification processes and regenerative capacity can greatly differ in mandible and femur. OBJECTIVE Mesenchymal stem cells from cranial and postcranial bones are of different embryologic origin. This may be the reason why the regenerative capacity differs between cranial and postcranial bones in old patients. It was hypothesised that different ageing patterns, reflected by osteocyte density, lacunar density and osteoid formation, exist between murine mandibles and femurs. MATERIAL AND METHODS Mandible and femur of young (4 months) and old (34-36 months old) male C57Bl/6 mice were histologically investigated to determine the number of lacunae occupied with osteocytes. Osteoid formation was revealed by Masson-Goldner staining, and the spatial distribution of BMP-2 synthesis was examined. RESULTS Over lifetime, the number of lacunae occupied with osteocytes only showed a modest decrease in mandibular bone (old 85.63%/young 91.12%) while greatly diverging in the femur (old 55.99%/young 93.28%). In equal measure, old femur exhibited less osteoid formation and decreased BMP-2 expression. CONCLUSION Tissue-specific conduct of bone ageing is moulded by osteocytic activities, which was found to vary between postcranial and craniofacial skeleton. The latter harbours long-lived osteocytes also in old animals which assures lifelong bone integrity. Preliminary concurring findings from a human cadaver, also presented in this contribution, provided a rationale for recommending the translatability to humans.
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Affiliation(s)
- Robert G Stigler
- Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - Kathrin Becker
- Department of Orthodontics, Universitätsklinikum Düsseldorf, Düsseldorf, Germany
| | - Frank R Kloss
- Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - Robert Gassner
- Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - Günter Lepperdinger
- Division of Genetics, Department of Cell Biology and Physiology, Faculty of Natural Sciences, University Salzburg, Salzburg, Austria
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Giuliani A, Iezzi G, Mozzati M, Gallesio G, Mazzoni S, Tromba G, Zanini F, Piattelli A, Mortellaro C. Bisphosphonate-related osteonecrosis of the human jaw: A combined 3D assessment of bone descriptors by histology and synchrotron radiation-based microtomography. Oral Oncol 2018; 82:200-202. [PMID: 29752002 DOI: 10.1016/j.oraloncology.2018.04.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 04/28/2018] [Accepted: 04/30/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Alessandra Giuliani
- Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
| | - Giovanna Iezzi
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti Scalo, CH, Italy.
| | - Marco Mozzati
- SIOM Oral Surgery and Implantology Center, Torino, Italy.
| | | | - Serena Mazzoni
- Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
| | | | - Franco Zanini
- Elettra Sincrotrone Trieste S.C.p.A, Trieste, Italy.
| | - Adriano Piattelli
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti Scalo, CH, Italy.
| | - Carmen Mortellaro
- Science Department, Department of Health Sciences ''A. Avogadro", University of Eastern Piedmont, Novara, Italy.
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Microstructural changes associated with osteoporosis negatively affect loading-induced fluid flow around osteocytes in cortical bone. J Biomech 2017; 66:127-136. [PMID: 29217091 DOI: 10.1016/j.jbiomech.2017.11.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 11/05/2017] [Accepted: 11/09/2017] [Indexed: 12/21/2022]
Abstract
Loading-induced interstitial fluid flow in the microporosities of bone is critical for osteocyte mechanotransduction and for the maintenance of tissue health, enhancing convective transport in the lacunar-canalicular system. In recent studies, our group has reported alterations of bone's vascular porosity and lacunar-canalicular system microarchitecture in a rat model of postmenopausal osteoporosis. In this work, poroelastic finite element analysis was used to investigate whether these microstructural changes can affect interstitial fluid flow around osteocytes. Animal-specific finite element models were developed combining micro-CT reconstructions of bone microstructure and measures of the poroelastic material properties. These models were used to quantify and compare loading-induced fluid flow in the lacunar-canalicular system of ovariectomized and sham-operated rats. A parametric analysis was also used to quantify the influence of the lacunar-canalicular permeability and vascular porosity on the fluid velocity magnitude. Results show that mechanically-induced interstitial fluid velocity can be significantly reduced in the lacunar-canalicular system of ovariectomized rats. Interestingly, the vascular porosity is shown to have a major influence on interstitial fluid flow, while the lacunar-canalicular permeability influence is limited when larger than 10-20m2. Altogether our results suggest that microstructural changes associated with the osteoporotic condition can negatively affect interstitial fluid flow around osteocytes in the lacunar-canalicular system of cortical bone. This fluid flow reduction could impair mechanosensation of the osteocytic network, possibly playing a role in the initiation and progression of age-related bone loss and postmenopausal osteoporosis.
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Florczyk SJ, Simon M, Juba D, Pine PS, Sarkar S, Chen D, Baker PJ, Bodhak S, Cardone A, Brady MC, Bajcsy P, Simon CG. A Bioinformatics 3D Cellular Morphotyping Strategy for Assessing Biomaterial Scaffold Niches. ACS Biomater Sci Eng 2017; 3:2302-2313. [PMID: 33445289 DOI: 10.1021/acsbiomaterials.7b00473] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many biomaterial scaffolds have been advanced to provide synthetic cell niches for tissue engineering and drug screening applications; however, current methods for comparing scaffold niches focus on cell functional outcomes or attempt to normalize materials properties between different scaffold formats. We demonstrate a three-dimensional (3D) cellular morphotyping strategy for comparing biomaterial scaffold cell niches between different biomaterial scaffold formats. Primary human bone marrow stromal cells (hBMSCs) were cultured on 8 different biomaterial scaffolds, including fibrous scaffolds, hydrogels, and porous sponges, in 10 treatment groups to compare a variety of biomaterial scaffolds and cell morphologies. A bioinformatics approach was used to determine the 3D cellular morphotype for each treatment group by using 82 shape metrics to analyze approximately 1000 cells. We found that hBMSCs cultured on planar substrates yielded planar cell morphotypes, while those cultured in 3D scaffolds had elongated or equiaxial cellular morphotypes with greater height. Multivariate analysis was effective at distinguishing mean shapes of cells in flat substrates from cells in scaffolds, as was the metric L1-depth (the cell height along its shortest axis after aligning cells with a characteristic ellipsoid). The 3D cellular morphotyping technique enables direct comparison of cellular microenvironments between widely different types of scaffolds and design of scaffolds based on cell structure-function relationships.
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Affiliation(s)
| | | | | | | | | | - Desu Chen
- Biophysics Program, University of Maryland, College Park, Maryland 20742, United States
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Abstract
PURPOSE OF REVIEW The bone is able to adapt its structure to mechanical signals via the bone remodeling process governed by mechanosensitive osteocytes. With aging, an imbalance in bone remodeling results in osteoporosis. In this review, we hypothesized that changes in lacunar morphology underlie the decreased bone mechanoresponsiveness to mechanical loading with aging. RECENT FINDINGS Several studies have reported considerable variations in the shape of osteocytes and their lacunae with aging. Since osteocytes can sense matrix strain directly via their cell bodies, the variations in osteocyte morphology may cause changes in osteocyte mechanosensitivity. As a consequence, the load-adaptive response of osteocytes may change with aging, even when mechanical loading would remain unchanged. Though extensive quantitative data is lacking, evidence exists that the osteocyte lacunae are becoming smaller and more spherical with aging. Future dedicated studies might reveal whether these changes would affect osteocyte mechanosensation and the subsequent biological response, and whether this is (one of) the pathways involved in age-related bone loss.
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Affiliation(s)
- Haniyeh Hemmatian
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Celestijnenlaan 300c, 3001 Leuven, Belgium
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Astrid D. Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - G. Harry van Lenthe
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Celestijnenlaan 300c, 3001 Leuven, Belgium
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Hemmatian H, Laurent MR, Ghazanfari S, Vanderschueren D, Bakker AD, Klein-Nulend J, van Lenthe GH. Accuracy and reproducibility of mouse cortical bone microporosity as quantified by desktop microcomputed tomography. PLoS One 2017; 12:e0182996. [PMID: 28797125 PMCID: PMC5552254 DOI: 10.1371/journal.pone.0182996] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/27/2017] [Indexed: 02/07/2023] Open
Abstract
Bone's microporosity plays important roles in bone biology and bone mechanical quality. In this study, we explored the accuracy and reproducibility of nondestructive desktop μCT for 3D visualization and subsequent morphometric analysis of mouse cortical bone microporosity including the vascular canal network and osteocyte lacunae. The accuracy of measurements was evaluated in five murine fibula using confocal laser scanning microscopy (CLSM) in conjunction with Fluorescein isothiocyanate (FITC) staining as the reference method. The reproducibility of μCT-derived cortical bone microstructural indices was examined in 10 fibulae of C57Bl/6J male mice at a nominal resolution of 700 nanometer. Three repeated measurements were made on different days. An excellent correlation between μCT and CLSM was observed for both mean lacuna volume (r = 0.98, p = 0.002) and for mean lacuna orientation (r = 0.93, p = 0.02). Whereas the two techniques showed no significant differences for these parameters, the mean lacuna sphericity acquired from μCT was significantly higher than CLSM (p = 0.01). Reproducibility was high, with precision errors (PE) of 1.57-4.69% for lacuna parameters, and of 1.01-9.45% for vascular canal parameters. Intraclass correlation coefficient (ICC) showed a high reliability of the measurements, ranging from 0.998-1.000 for cortical parameters, 0.973-0.999 for vascular canal parameters and 0.755-0.991 for lacuna parameters. In conclusion, desktop μCT is a valuable tool to quantify the 3D characteristics of bone vascular canals as well as lacunae which can be applied to intact murine bones with high accuracy and reproducibility. Thus, μCT might be an important tool to improve our understanding of the physiological and biomechanical significance of these cannular and lacunar structure in cortical bone.
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Affiliation(s)
- Haniyeh Hemmatian
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Michaël R. Laurent
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
- Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Samaneh Ghazanfari
- Aachen-Maastricht Institute for Biobased Materials, Department of Humanities and Sciences, Maastricht University, Geleen, The Netherlands
| | - Dirk Vanderschueren
- Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Astrid D. Bakker
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Jenneke Klein-Nulend
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - G. Harry van Lenthe
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
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50
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Ashique AM, Hart LS, Thomas CDL, Clement JG, Pivonka P, Carter Y, Mousseau DD, Cooper DML. Lacunar-canalicular network in femoral cortical bone is reduced in aged women and is predominantly due to a loss of canalicular porosity. Bone Rep 2017; 7:9-16. [PMID: 28752112 PMCID: PMC5517690 DOI: 10.1016/j.bonr.2017.06.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/29/2017] [Accepted: 06/27/2017] [Indexed: 11/29/2022] Open
Abstract
The lacunar-canalicular network (LCN) of bone contains osteocytes and their dendritic extensions, which allow for intercellular communication, and are believed to serve as the mechanosensors that coordinate the processes of bone modeling and remodeling. Imbalances in remodeling, for example, are linked to bone disease, including fragility associated with aging. We have reported that there is a reduction in scale for one component of the LCN, osteocyte lacunar volume, across the human lifespan in females. In the present study, we explore the hypothesis that canalicular porosity also declines with age. To visualize the LCN and to determine how its components are altered with aging, we examined samples from young (age: 20–23 y; n = 5) and aged (age: 70–86 y; n = 6) healthy women donors utilizing a fluorescent labelling technique in combination with confocal laser scanning microscopy. A large cross-sectional area of cortical bone spanning the endosteal to periosteal surfaces from the anterior proximal femoral shaft was examined in order to account for potential trans-cortical variation in the LCN. Overall, we found that LCN areal fraction was reduced by 40.6% in the samples from aged women. This reduction was due, in part, to a reduction in lacunar density (21.4% decline in lacunae number per given area of bone), but much more so due to a 44.6% decline in canalicular areal fraction. While the areal fraction of larger vascular canals was higher in endosteal vs. periosteal regions for both age groups, no regional differences were observed in the areal fractions of the LCN and its components for either age group. Our data indicate that the LCN is diminished in aged women, and is largely due to a decline in the canalicular areal fraction, and that, unlike vascular canal porosity, this diminished LCN is uniform across the cortex. The lacunar-canalicular network (LCN) is reduced by 40.6% in aged women The lacunar density (lacunae number per given area of bone) is reduced by 21.4% in aged women The reduction in LCN in aged women is primarily due to a 44.6% loss of canaliculi No endosteal vs. periosteal regional differences were observed in the LCN and its components in either young or aged women A reduction in canaliculi with age may contribute to bone fragility in aged women
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Affiliation(s)
- A M Ashique
- Department of Anatomy & Cell Biology, University of Saskatchewan, Saskatoon, SK, Canada
| | - L S Hart
- Department of Anatomy & Cell Biology, University of Saskatchewan, Saskatoon, SK, Canada
| | - C D L Thomas
- Melbourne Dental School, University of Melbourne, Melbourne, VIC, Australia
| | - J G Clement
- Melbourne Dental School, University of Melbourne, Melbourne, VIC, Australia
| | - P Pivonka
- St. Vincent's Department of Surgery, University of Melbourne, Melbourne, VIC, Australia.,School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Y Carter
- Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA
| | - D D Mousseau
- Department of Psychiatry, University of Saskatchewan, Saskatoon, SK, Canada
| | - D M L Cooper
- Department of Anatomy & Cell Biology, University of Saskatchewan, Saskatoon, SK, Canada
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