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Mechanobiology of the Human Intervertebral Disc: Systematic Review of the Literature and Future Perspectives. Int J Mol Sci 2023; 24:ijms24032728. [PMID: 36769050 PMCID: PMC9917554 DOI: 10.3390/ijms24032728] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/21/2023] [Accepted: 01/24/2023] [Indexed: 02/04/2023] Open
Abstract
Low back pain is an extremely common condition with severe consequences. Among its potential specific causes, degenerative disc disease (DDD) is one of the most frequently observed. Mechanobiology is an emerging science studying the interplay between mechanical stimuli and the biological behavior of cells and tissues. The aim of the presented study is to review, with a systematic approach, the existing literature regarding the mechanobiology of the human intervertebral disc (IVD), define the main pathways involved in DDD and identify novel potential therapeutic targets. The review was carried out in accordance with the Preferential Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were included if they described biological responses of human IVD cells under mechanical stimulation or alterations of mechanical properties of the IVD determined by different gene expression. Fifteen studies were included and showed promising results confirming the mechanobiology of the human IVD as a key element in DDD. The technical advances of the last decade have allowed us to increase our understanding of this topic, enabling us to identify possible therapeutic targets to treat and to prevent DDD. Further research and technological innovations will shed light on the interactions between the mechanics and biology of the human IVD.
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Yu P, Mao F, Chen J, Ma X, Dai Y, Liu G, Dai F, Liu J. Characteristics and mechanisms of resorption in lumbar disc herniation. Arthritis Res Ther 2022; 24:205. [PMID: 35999644 PMCID: PMC9396855 DOI: 10.1186/s13075-022-02894-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 07/26/2022] [Indexed: 12/12/2022] Open
Abstract
Lumbar disc herniation (LDH) can be spontaneously absorbed without surgical treatment. However, the pathogenesis and physiological indications for predicting protrusion reabsorption are still unclear, which prevents clinicians from preferentially choosing conservative treatment options for LDH patients with reabsorption effects. The purpose of this review was to summarize previous reports on LDH reabsorption and to discuss the clinical and imaging features that favor natural absorption. We highlighted the biological mechanisms involved in the phenomenon of LDH reabsorption, including macrophage infiltration, inflammatory responses, matrix remodeling, and neovascularization. In addition, we summarized and discussed potential clinical treatments for promoting reabsorption. Current evidence suggests that macrophage regulation of inflammatory mediators, matrix metalloproteinases, and specific cytokines in intervertebral disc is essential for the spontaneous reabsorption of LDH.
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Affiliation(s)
- Pengfei Yu
- Department of Orthopaedic Surgery, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, 215009, People's Republic of China
| | - Feng Mao
- Department of Orthopaedic Surgery, Kunshan Integrated TCM and Western Medicine Hospital, Suzhou, 215332, People's Republic of China
| | - Jingyun Chen
- State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Xiaoying Ma
- State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Yuxiang Dai
- Department of Orthopaedic Surgery, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, 215009, People's Republic of China
| | - Guanhong Liu
- Department of Orthopaedic Surgery, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, 215009, People's Republic of China
| | - Feng Dai
- Department of Orthopaedic Surgery, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, 215009, People's Republic of China
| | - Jingtao Liu
- Department of Orthopaedic Surgery, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, 215009, People's Republic of China.
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3
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Li W, Zhang S, Wang D, Zhang H, Shi Q, Zhang Y, Wang M, Ding Z, Xu S, Gao B, Yan M. Exosomes Immunity Strategy: A Novel Approach for Ameliorating Intervertebral Disc Degeneration. Front Cell Dev Biol 2022; 9:822149. [PMID: 35223870 PMCID: PMC8870130 DOI: 10.3389/fcell.2021.822149] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 12/21/2021] [Indexed: 12/11/2022] Open
Abstract
Low back pain (LBP), which is one of the most severe medical and social problems globally, has affected nearly 80% of the population worldwide, and intervertebral disc degeneration (IDD) is a common musculoskeletal disorder that happens to be the primary trigger of LBP. The pathology of IDD is based on the impaired homeostasis of catabolism and anabolism in the extracellular matrix (ECM), uncontrolled activation of immunologic cascades, dysfunction, and loss of nucleus pulposus (NP) cells in addition to dynamic cellular and biochemical alterations in the microenvironment of intervertebral disc (IVD). Currently, the main therapeutic approach regarding IDD is surgical intervention, but it could not considerably cure IDD. Exosomes, extracellular vesicles with a diameter of 30–150 nm, are secreted by various kinds of cell types like stem cells, tumor cells, immune cells, and endothelial cells; the lipid bilayer of the exosomes protects them from ribonuclease degradation and helps improve their biological efficiency in recipient cells. Increasing lines of evidence have reported the promising applications of exosomes in immunological diseases, and regarded exosomes as a potential therapeutic source for IDD. This review focuses on clarifying novel therapies based on exosomes derived from different cell sources and the essential roles of exosomes in regulating IDD, especially the immunologic strategy.
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Affiliation(s)
- Weihang Li
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Shilei Zhang
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Dong Wang
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
- Department of Orthopaedics, Affiliated Hospital of Yanan University, Yanan, China
| | - Huan Zhang
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Quan Shi
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Yuyuan Zhang
- Department of Critical Care Medicine, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Mo Wang
- The First Brigade of Basic Medical College, Air Force Military Medical University, Xi’an, China
| | - Ziyi Ding
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Songjie Xu
- Beijing Luhe Hospital, Capital Medical University, Beijing, China
- *Correspondence: Songjie Xu, ; Bo Gao, ; Ming Yan,
| | - Bo Gao
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
- *Correspondence: Songjie Xu, ; Bo Gao, ; Ming Yan,
| | - Ming Yan
- Department of Orthopedic Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
- *Correspondence: Songjie Xu, ; Bo Gao, ; Ming Yan,
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4
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Applications of Functionalized Hydrogels in the Regeneration of the Intervertebral Disc. BIOMED RESEARCH INTERNATIONAL 2021; 2021:2818624. [PMID: 34458364 PMCID: PMC8397561 DOI: 10.1155/2021/2818624] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 07/26/2021] [Indexed: 02/08/2023]
Abstract
Intervertebral disc degeneration (IDD) is caused by genetics, aging, and environmental factors and is one of the leading causes of low back pain. The treatment of IDD presents many challenges. Hydrogels are biomaterials that possess properties similar to those of the natural extracellular matrix and have significant potential in the field of regenerative medicine. Hydrogels with various functional qualities have recently been used to repair and regenerate diseased intervertebral discs. Here, we review the mechanisms of intervertebral disc homeostasis and degeneration and then discuss the applications of hydrogel-mediated repair and intervertebral disc regeneration. The classification of artificial hydrogels and natural hydrogels is then briefly introduced, followed by an update on the development of functional hydrogels, which include noncellular therapeutic hydrogels, cellular therapeutic hydrogel scaffolds, responsive hydrogels, and multifunctional hydrogels. The challenges faced and future developments of the hydrogels used in IDD are discussed as they further promote their clinical translation.
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5
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Morris H, Gonçalves CF, Dudek M, Hoyland J, Meng QJ. Tissue physiology revolving around the clock: circadian rhythms as exemplified by the intervertebral disc. Ann Rheum Dis 2021; 80:828-839. [PMID: 33397731 DOI: 10.1136/annrheumdis-2020-219515] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 01/07/2023]
Abstract
Circadian clocks in the brain and peripheral tissues temporally coordinate local physiology to align with the 24 hours rhythmic environment through light/darkness, rest/activity and feeding/fasting cycles. Circadian disruptions (during ageing, shift work and jet-lag) have been proposed as a risk factor for degeneration and disease of tissues, including the musculoskeletal system. The intervertebral disc (IVD) in the spine separates the bony vertebrae and permits movement of the spinal column. IVD degeneration is highly prevalent among the ageing population and is a leading cause of lower back pain. The IVD is known to experience diurnal changes in loading patterns driven by the circadian rhythm in rest/activity cycles. In recent years, emerging evidence indicates the existence of molecular circadian clocks within the IVD, disruption to which accelerates tissue ageing and predispose animals to IVD degeneration. The cell-intrinsic circadian clocks in the IVD control key aspects of physiology and pathophysiology by rhythmically regulating the expression of ~3.5% of the IVD transcriptome, allowing cells to cope with the drastic biomechanical and chemical changes that occur throughout the day. Indeed, epidemiological studies on long-term shift workers have shown an increased incidence of lower back pain. In this review, we summarise recent findings of circadian rhythms in health and disease, with the IVD as an exemplar tissue system. We focus on rhythmic IVD functions and discuss implications of utilising biological timing mechanisms to improve tissue health and mitigate degeneration. These findings may have broader implications in chronic rheumatic conditions, given the recent findings of musculoskeletal circadian clocks.
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Affiliation(s)
- Honor Morris
- Wellcome Centre for Cell Matrix Research, University of Manchester, Manchester, UK.,Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Cátia F Gonçalves
- Wellcome Centre for Cell Matrix Research, University of Manchester, Manchester, UK.,Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Michal Dudek
- Wellcome Centre for Cell Matrix Research, University of Manchester, Manchester, UK.,Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Judith Hoyland
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, University of Manchester, Manchester, UK .,NIHR Manchester Musculoskeletal Biomedical Research Centre, Manchester University, NHS Foundation Trust, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Qing-Jun Meng
- Wellcome Centre for Cell Matrix Research, University of Manchester, Manchester, UK .,Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, University of Manchester, Manchester, UK
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6
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Zhao R, Liu W, Xia T, Yang L. Disordered Mechanical Stress and Tissue Engineering Therapies in Intervertebral Disc Degeneration. Polymers (Basel) 2019; 11:polym11071151. [PMID: 31284436 PMCID: PMC6680713 DOI: 10.3390/polym11071151] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/27/2019] [Accepted: 07/01/2019] [Indexed: 12/11/2022] Open
Abstract
Low back pain (LBP), commonly induced by intervertebral disc degeneration, is a lumbar disease with worldwide prevalence. However, the mechanism of degeneration remains unclear. The intervertebral disc is a nonvascular organ consisting of three components: Nucleus pulposus, annulus fibrosus, and endplate cartilages. The disc is structured to support our body motion and endure persistent external mechanical pressure. Thus, there is a close connection between force and intervertebral discs in LBP. It is well established that with aging, disordered mechanical stress profoundly influences the fate of nucleus pulposus and the alignment of collagen fibers in the annulus fibrosus. These support a new understanding that disordered mechanical stress plays an important role in the degeneration of the intervertebral discs. Tissue-engineered regenerative and reparative therapies are being developed for relieving disc degeneration and symptoms of lower back pain. In this paper, we will review the current literature available on the role of disordered mechanical stress in intervertebral disc degeneration, and evaluate the existing tissue engineering treatment strategies of the current therapies.
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Affiliation(s)
- Runze Zhao
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China
| | - Wanqian Liu
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China
| | - Tingting Xia
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China.
| | - Li Yang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China.
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Elsaadany M, Winters K, Adams S, Stasuk A, Ayan H, Yildirim-Ayan E. Equiaxial Strain Modulates Adipose-derived Stem Cell Differentiation within 3D Biphasic Scaffolds towards Annulus Fibrosus. Sci Rep 2017; 7:12868. [PMID: 28993681 PMCID: PMC5634474 DOI: 10.1038/s41598-017-13240-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 09/19/2017] [Indexed: 12/14/2022] Open
Abstract
Recurrence of intervertebral disc (IVD) herniation is the most important factor leading to chronic low back pain and subsequent disability after discectomy. Efficacious annulus fibrosus (AF) repair strategy that delivers cells and biologics to IVD injury site is needed to limit the progression of disc degeneration and promote disc self-regeneration capacities after discectomy procedures. In this study, a biphasic mechanically-conditioned scaffold encapsulated with human adipose-derived stem cells (ASCs) is studied as a potential treatment strategy for AF defects. Equiaxial strains and frequencies were applied to ASCs-encapsulated scaffolds to identify the optimal loading modality to induce AF differentiation. Equiaxial loading resulted in 2–4 folds increase in secretion of extracellular matrix proteins and the reorganization of the matrix fibers and elongations of the cells along the load direction. Further, the equiaxial load induced region-specific differentiation of ASCs within the inner and outer regions of the biphasic scaffolds. Gene expression of AF markers was upregulated with 5–30 folds within the equiaxially loaded biphasic scaffolds compared to unstrained samples. The results suggest that there is a specific value of equiaxial strain favorable to differentiate ASCs towards AF lineage and that ASCs-embedded biphasic scaffold can potentially be utilized to repair the AF defects.
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Affiliation(s)
| | - Kayla Winters
- Department of Bioengineering, University of Toledo, Toledo, OH, USA
| | - Sarah Adams
- Department of Bioengineering, University of Toledo, Toledo, OH, USA
| | - Alexander Stasuk
- Department of Bioengineering, University of Toledo, Toledo, OH, USA
| | - Halim Ayan
- Department of Bioengineering, University of Toledo, Toledo, OH, USA
| | - Eda Yildirim-Ayan
- Department of Bioengineering, University of Toledo, Toledo, OH, USA.
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8
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Matta A, Karim MZ, Isenman DE, Erwin WM. Molecular Therapy for Degenerative Disc Disease: Clues from Secretome Analysis of the Notochordal Cell-Rich Nucleus Pulposus. Sci Rep 2017; 7:45623. [PMID: 28358123 PMCID: PMC5372366 DOI: 10.1038/srep45623] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 03/01/2017] [Indexed: 12/13/2022] Open
Abstract
Degenerative disc disease (DDD) is associated with spinal pain often leading to long-term disability. However, the non-chondrodystrophic canine intervertebral disc is protected from the development of DDD, ostensibly due to its retention of notochordal cells (NC) in the nucleus pulposus (NP). In this study, we hypothesized that secretome analysis of the NC-rich NP will lead to the identification of key proteins that delay the onset of DDD. Using mass-spectrometry, we identified 303 proteins including components of TGFβ- and Wnt-signaling, anti-angiogeneic factors and proteins that inhibit axonal ingrowth in the bioactive fractions of serum free, notochordal cell derived conditioned medium (NCCM). Ingenuity Pathway Analysis revealed TGFβ1 and CTGF as major hubs in protein interaction networks. In vitro treatment with TGFβ1 and CTGF promoted the synthesis of healthy extra-cellular matrix proteins, increased cell proliferation and reduced cell death in human degenerative disc NP cells. A single intra-discal injection of recombinant TGFβ1 and CTGF proteins in a pre-clinical rat-tail disc injury model restored the NC and stem cell rich NP. In conclusion, we demonstrate the potential of TGFβ1 and CTGF to mitigate the progression of disc degeneration and the potential use of these molecules in a molecular therapy to treat the degenerative disc.
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Affiliation(s)
- Ajay Matta
- Krembil Research Institute, Toronto Western Hospital, Toronto, Ontario, Canada
| | - M Zia Karim
- Krembil Research Institute, Toronto Western Hospital, Toronto, Ontario, Canada
| | - David E Isenman
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - W Mark Erwin
- Krembil Research Institute, Toronto Western Hospital, Toronto, Ontario, Canada.,Department of Surgery, University of Toronto, Toronto, Ontario, Canada.,Division of Research, Canadian Memorial Chiropractic College, Canada
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9
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Cyclic tensile stress of human annulus fibrosus cells induces MAPK activation: involvement in proinflammatory gene expression. Osteoarthritis Cartilage 2016; 24:679-87. [PMID: 26687822 DOI: 10.1016/j.joca.2015.11.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 11/05/2015] [Accepted: 11/24/2015] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To study the role of mitogen-activated protein kinases (MAPKs) in human annulus fibrosus (AF) cells subjected to cyclic tensile stress (CTS). DESIGN An in vitro system for CTS studies was established using AF cultures on fibronectin-coated silicone dishes. MAPK phosphorylation was studied by western analysis, while gene expression was followed by qRT-PCR. DNA synthesis was assessed by both tritiated thymidine incorporation and flow cytometry, and collagen synthesis using tritiated proline incorporation and the protease-free collagenase method. RESULTS All three MAPKs studied, i.e., ERK, SAPK/JNK, and p38 were found to be phosphorylated immediately after CTS application within physiological range. A second wave of phosphorylation appeared at later time points. MAPK activation was elevated at higher CTS magnitudes, but independent of the frequency. CTS did not stimulate DNA synthesis neither extracellular matrix turnover, but it stimulated the proinflammatory genes, COX-2, IL-6, and IL-8. This stimulation was more intense at the highest magnitude (8%) tested and at the median frequency (1 Hz) and time interval (12 h). Blocking of ERK, SAPK/JNK, and p38 MAPK inhibited the CTS-induced stimulation of COX-2 and IL-8, while IL-6 expression was mediated only by SAPK/JNK and p38 MAPK. CONCLUSIONS We have described for the first time the activation of MAPKs in human AF cells in response to CTS and showed that it drives an inflammatory reaction. These observations shed light on the mechanisms of intervertebral disc (IVD) cell responses to mechanical stress, contributing to the understanding of disc pathophysiology and possibly to the design of novel therapeutic interventions.
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10
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Temporal Analyses of the Response of Intervertebral Disc Cells and Mesenchymal Stem Cells to Nutrient Deprivation. Stem Cells Int 2016; 2016:5415901. [PMID: 26977156 PMCID: PMC4764757 DOI: 10.1155/2016/5415901] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 11/05/2015] [Accepted: 12/24/2015] [Indexed: 01/08/2023] Open
Abstract
Much emphasis has been placed recently on the repair of degenerate discs using implanted cells, such as disc cells or bone marrow derived mesenchymal stem cells (MSCs). This study examines the temporal response of bovine and human nucleus pulposus (NP) cells and MSCs cultured in monolayer following exposure to altered levels of glucose (0, 3.15, and 4.5 g/L) and foetal bovine serum (0, 10, and 20%) using an automated time-lapse imaging system. NP cells were also exposed to the cell death inducers, hydrogen peroxide and staurosporine, in comparison to serum starvation. We have demonstrated that human NP cells show an initial “shock” response to reduced nutrition (glucose). However, as time progresses, NP cells supplemented with serum recover with minimal evidence of cell death. Human NP cells show no evidence of proliferation in response to nutrient supplementation, whereas MSCs showed greater response to increased nutrition. When specifically inducing NP cell death with hydrogen peroxide and staurosporine, as expected, the cell number declined. These results support the concept that implanted NP cells or MSCs may be capable of survival in the nutrient-poor environment of the degenerate human disc, which has important clinical implications for the development of IVD cell therapies.
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11
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Kaspiris A, Chronopoulos E, Grivas TB, Vasiliadis E, Khaldi L, Lamprou M, Lelovas PP, Papaioannou N, Dontas IA, Papadimitriou E. Effects of mechanical loading on the expression of pleiotrophin and its receptor protein tyrosine phosphatase beta/zeta in a rat spinal deformity model. Cytokine 2015; 78:7-15. [PMID: 26615567 DOI: 10.1016/j.cyto.2015.11.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 11/09/2015] [Accepted: 11/14/2015] [Indexed: 11/16/2022]
Abstract
Mechanical loading of the spine is a major causative factor of degenerative changes and causes molecular and structural changes in the intervertebral disc (IVD) and the vertebrae end plate (EP). Pleiotrophin (PTN) is a growth factor with a putative role in bone remodeling through its receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ). The present study investigates the effects of strain on PTN and RPTPβ/ζ protein expression in vivo. Tails of eight weeks old Sprague-Dawley rats were subjected to mechanical loading using a mini Ilizarov external apparatus. Rat tails untreated (control) or after 0 degrees of compression and 10°, 30° and 50° of angulation (groups 0, I, II and III respectively) were studied. PTN and RPTPβ/ζ expression were evaluated using immunohistochemistry and Western blot analysis. In the control group, PTN was mostly expressed by the EP hypertrophic chondrocytes. In groups 0 to II, PTN expression was increased in the chondrocytes of hypertrophic and proliferating zones, as well as in osteocytes and osteoblast-like cells of the ossification zone. In group III, only limited PTN expression was observed in osteocytes. RPTPβ/ζ expression was increased mainly in group 0, but also in group I, in all types of cells. Low intensity RPTPβ/ζ immunostaining was observed in groups II and III. Collectively, PTN and RPTPβ/ζ are expressed in spinal deformities caused by mechanical loading, and their expression depends on the type and severity of the applied strain.
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Affiliation(s)
- Angelos Kaspiris
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Patras, Patras 26504, Greece; Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece
| | - Efstathios Chronopoulos
- Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece; Second Department of Orthopaedic Surgery, Konstantopoulio General Hospital and Medical School, University of Athens, Athens 14233, Greece
| | - Theodoros B Grivas
- Department of Orthopaedics, Tzanio General Hospital of Piraeus-NHS, Piraeus 18536, Greece
| | - Elias Vasiliadis
- Third Department of Orthopaedics, KAT General Hospital, School of Medicine, University of Athens, Athens 14561, Greece
| | - Lubna Khaldi
- Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece
| | - Margarita Lamprou
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Patras, Patras 26504, Greece
| | - Pavlos P Lelovas
- Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece
| | - Nikolaos Papaioannou
- Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece
| | - Ismene A Dontas
- Laboratory for Research of the Musculoskeletal System, School of Medicine, University of Athens, Athens 14561, Greece
| | - Evangelia Papadimitriou
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Patras, Patras 26504, Greece.
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12
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Tsaryk R, Gloria A, Russo T, Anspach L, De Santis R, Ghanaati S, Unger RE, Ambrosio L, Kirkpatrick CJ. Collagen-low molecular weight hyaluronic acid semi-interpenetrating network loaded with gelatin microspheres for cell and growth factor delivery for nucleus pulposus regeneration. Acta Biomater 2015; 20:10-21. [PMID: 25861947 DOI: 10.1016/j.actbio.2015.03.041] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 03/07/2015] [Accepted: 03/18/2015] [Indexed: 12/19/2022]
Abstract
Intervertebral disc (IVD) degeneration is one of the main causes of low back pain. Current surgical treatments are complex and generally do not fully restore spine mobility. Development of injectable extracellular matrix-based hydrogels offers an opportunity for minimally invasive treatment of IVD degeneration. Here we analyze a specific formulation of collagen-low molecular weight hyaluronic acid (LMW HA) semi-interpenetrating network (semi-IPN) loaded with gelatin microspheres as a potential material for tissue engineering of the inner part of the IVD, the nucleus pulposus (NP). The material displayed a gel-like behavior, it was easily injectable as demonstrated by suitable tests and did not induce cytotoxicity or inflammation. Importantly, it supported the growth and chondrogenic differentiation potential of mesenchymal stem cells (MSC) and nasal chondrocytes (NC) in vitro and in vivo. These properties of the hydrogel were successfully combined with TGF-β3 delivery by gelatin microspheres, which promoted the chondrogenic phenotype. Altogether, collagen-LMW HA loaded with gelatin microspheres represents a good candidate material for NP tissue engineering as it combines important rheological, functional and biological features.
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13
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Binch ALA, Cole AA, Breakwell LM, Michael ALR, Chiverton N, Cross AK, Le Maitre CL. Expression and regulation of neurotrophic and angiogenic factors during human intervertebral disc degeneration. Arthritis Res Ther 2014; 16:416. [PMID: 25209447 PMCID: PMC4177417 DOI: 10.1186/s13075-014-0416-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 08/01/2014] [Indexed: 12/19/2022] Open
Abstract
Introduction The degenerate intervertebral disc (IVD) becomes innervated by sensory nerve fibres, and vascularised by blood vessels. This study aimed to identify neurotrophins, neuropeptides and angiogenic factors within native IVD tissue and to further investigate whether pro-inflammatory cytokines are involved in the regulation of expression levels within nucleus pulposus (NP) cells, nerve and endothelial cells. Methods Quantitative real-time PCR (qRT-PCR) was performed on 53 human IVDs from 52 individuals to investigate native gene expression of neurotrophic factors and their receptors, neuropeptides and angiogenic factors. The regulation of these factors by cytokines was investigated in NP cells in alginate culture, and nerve and endothelial cells in monolayer using RT-PCR and substance P (SP) protein expression in interleukin-1 (IL-1β) stimulated NP cells. Results Initial investigation on uncultured NP cells identified expression of all neurotrophins by native NP cells, whilst the nerve growth factor (NGF) receptor was only identified in severely degenerate and infiltrated discs, and brain derived neurotrophic factor (BDNF) receptor expressed by more degenerate discs. BDNF expression was significantly increased in infiltrated and degenerate samples. SP and vascular endothelial growth factor (VEGF) were higher in infiltrated samples. In vitro stimulation by IL-1β induced NGF in NP cells. Neurotropin-3 was induced by tumour necrosis factor alpha in human dermal microvascular endothelial cells (HDMECs). SP gene and protein expression was increased in NP cells by IL-1β. Calcitonin gene related peptide was increased in SH-SY5Y cells upon cytokine stimulation. VEGF was induced by IL-1β and interleukin-6 in NP cells, whilst pleiotrophin was decreased by IL-1β. VEGF and pleiotrophin were expressed by SH-SY5Y cells, and VEGF by HDMECs, but were not modulated by cytokines. Conclusions The release of cytokines, in particular IL-1β during IVD degeneration, induced significant increases in NGF and VEGF which could promote neuronal and vascular ingrowth. SP which is released into the matrix could potentially up regulate the production of matrix degrading enzymes and also sensitise nerves, resulting in nociceptive transmission and chronic low back pain. This suggests that IL-1β is a key regulatory cytokine, involved in the up regulation of factors involved in innervation and vascularisation of tissues.
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Kim SY, Park SH, Shin JW, Kang YG, Jeon KJ, Hyun JS, Oh MJ, Shin JW. Mechanical stimulation and the presence of neighboring cells greatly affect migration of human mesenchymal stem cells. Biotechnol Lett 2013; 35:1817-22. [DOI: 10.1007/s10529-013-1270-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 06/07/2013] [Indexed: 01/13/2023]
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Neidlinger-Wilke C, Galbusera F, Pratsinis H, Mavrogonatou E, Mietsch A, Kletsas D, Wilke HJ. Mechanical loading of the intervertebral disc: from the macroscopic to the cellular level. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2013; 23 Suppl 3:S333-43. [DOI: 10.1007/s00586-013-2855-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 05/10/2013] [Accepted: 06/03/2013] [Indexed: 12/24/2022]
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Relationship between neovascularization and degenerative changes in herniated lumbar intervertebral discs. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2013; 22:2474-80. [PMID: 23736847 DOI: 10.1007/s00586-013-2842-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 05/09/2013] [Accepted: 05/26/2013] [Indexed: 12/11/2022]
Abstract
PURPOSE Lumbar disc degeneration may be associated with intensity of neovascularization in disc herniations. Our study was designed to evaluate how much the severity of histodegeneration is related to the development of neovascularization and to the level of pleiotrophin in the herniated lumbar discs. METHODS Surgically excised lumbar disc specimens were obtained from 29 patients with noncontained (i.e., extruding through the posterior longitudinal ligament) and 21 patients with contained disc herniations. The histodegeneration scores and levels of neovascularization were estimated according to semiquantitative analysis in lumbar disc and endplate samples. Immunohistochemical staining were performed to identify the newly formed blood vessels and to detect the presence of pleiotrophin in the specimens. RESULTS Higher levels of disc and endplate neovascularity were registered in noncontained herniations. The level of neovascularization was significantly related to the score of histodegeneration in the herniated disc tissues but not in the endplate specimens. Both contained and noncontained herniations had the highest values of histodegeneration in conjunction with the highest level of neovascularization but the relations between neovascularity and degenerative changes remained to be significant only in the group of noncontained herniations. Registration or frequency of pleiotrophin positive cells did not correlate significantly with histodegeneration or level of neovascularization in the disc samples. CONCLUSION Severe histodegeneration of the lumbar disc herniations is associated with enhanced neovascularization and potentially also spontaneous regression of the herniated tissue.
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Shoukry M, Li J, Pei M. Reconstruction of an in vitro niche for the transition from intervertebral disc development to nucleus pulposus regeneration. Stem Cells Dev 2013; 22:1162-76. [PMID: 23259403 DOI: 10.1089/scd.2012.0597] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The nucleus pulposus (NP) plays a prominent role in both the onset and progression of intervertebral disc degeneration. While autologous repair strategies have demonstrated some success, their in vitro culture system is outdated and insufficient for maintaining optimally functioning cells through the required extensive passaging. Consequently, the final population of cells may be unsuitable for the overwhelming task of repairing tissue in vivo and could result in subpar clinical outcomes. Recent work has identified synovium-derived stem cells (SDSCs) as a potentially important new candidate. This population of precursors can promote matrix regeneration and additionally restore the balance of catabolic and anabolic metabolism of surrounding cells. Another promising application is their ability to produce an extracellular matrix in vitro that can be modified via decellularization to produce a tissue-specific substrate for efficient cell expansion, while retaining chondrogenic potential. When combined with hypoxia, soluble factors, and other environmental regulators, the resultant complex microenvironment will more closely resemble the in vivo niche, which further improves the cell capacity, even after extensive passaging. In this review, the adaptive mechanisms NP cells utilize in vivo are considered for insight into what factors are important for constructing a tissue-specific in vitro niche. Evidence for the use of SDSCs for NP regeneration is also discussed. Many aspects of NP behavior are still unknown, which could lead to future work yielding key information on producing sufficient numbers of a high-quality NP-specific population that is able to regenerate deteriorated NP in vivo.
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Affiliation(s)
- Mark Shoukry
- Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, Morgantown, West Virginia 26506-9196, USA
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Liao J, Ke M, Xu T, Lin L. Electroacupuncture inhibits apoptosis in annulus fibrosis cells through suppression of the mitochondria-dependent pathway in a rat model of cervical intervertebral disc degradation. Genet Mol Biol 2012; 35:686-92. [PMID: 23055810 PMCID: PMC3459421 DOI: 10.1590/s1415-47572012005000046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 05/09/2012] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to investigate whether treatment with electroacupuncture (EA) inhibited mitochondria-dependent apoptosis in annulus fibrosis (AF) cells in a rat model of cervical intervertebral disc degradation induced by unbalanced dynamic and static forces. Forty Sprague-Dawley rats were used in this study, of which 30 underwent surgery to induce cervical intervertebral disc degradation, 10 rats received EA at acupoints Dazhui (DU 14) and Shousanli (LI 10). TUNEL staining was measured to assess apoptosis in AF cells, immunohistochemistry was used to examine Bcl-2 and Bax expression, colorimetric assays were used to determine caspase 9 and caspase 3 activities and RT-PCR and western blotting were used to assess the mRNA and protein expression of Crk and ERK2. Treatment with EA reduced the number of AF-positive cells in TUNEL staining, increased Bcl-2-positive cells and decreased Bax-positive cells in immunohistochemical staining, significantly inhibited the activation of caspases-9 and -3, and enhanced the mRNA and protein expression of Crk and ERK2. Our data show that EA inhibits AF cell apoptosis via the mitochondria-dependent pathway and up-regulates Crk and ERK2 expression. These results suggest that treatment with may be a good alternative therapy for preventing cervical spondylosis.
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Affiliation(s)
- Jun Liao
- Department of Acupuncture and Moxa and Tuina, Fujian University of Traditional Chinese Medicine, Fujian, P.R. China
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Paul CPL, Zuiderbaan HA, Zandieh Doulabi B, van der Veen AJ, van de Ven PM, Smit TH, Helder MN, van Royen BJ, Mullender MG. Simulated-physiological loading conditions preserve biological and mechanical properties of caprine lumbar intervertebral discs in ex vivo culture. PLoS One 2012; 7:e33147. [PMID: 22427972 PMCID: PMC3302815 DOI: 10.1371/journal.pone.0033147] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 02/09/2012] [Indexed: 01/07/2023] Open
Abstract
Low-back pain (LBP) is a common medical complaint and associated with high societal costs. Degeneration of the intervertebral disc (IVD) is assumed to be an important causal factor of LBP. IVDs are continuously mechanically loaded and both positive and negative effects have been attributed to different loading conditions. In order to study mechanical loading effects, degeneration-associated processes and/or potential regenerative therapies in IVDs, it is imperative to maintain the IVDs' structural integrity. While in vivo models provide comprehensive insight in IVD biology, an accompanying organ culture model can focus on a single factor, such as loading and may serve as a prescreening model to reduce life animal testing. In the current study we examined the feasibility of organ culture of caprine lumbar discs, with the hypothesis that a simulated-physiological load will optimally preserve IVD properties. Lumbar caprine IVDs (n = 175) were cultured in a bioreactor up to 21 days either without load, low dynamic load (LDL), or with simulated-physiological load (SPL). IVD stiffness was calculated from measurements of IVD loading and displacement. IVD nucleus, inner- and outer annulus were assessed for cell viability, cell density and gene expression. The extracellular matrix (ECM) was analyzed for water, glycosaminoglycan and total collagen content. IVD biomechanical properties did not change significantly with loading conditions. With SPL, cell viability, cell density and gene expression were preserved up to 21 days. Both unloaded and LDL resulted in decreased cell viability, cell density and significant changes in gene expression, yet no differences in ECM content were observed in any group. In conclusion, simulated-physiological loading preserved the native properties of caprine IVDs during a 21-day culture period. The characterization of caprine IVD response to culture in the LDCS under SPL conditions paves the way for controlled analysis of degeneration- and regeneration-associated processes in the future.
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Affiliation(s)
- Cornelis P. L. Paul
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, VU University Medical Center, Amsterdam, The Netherlands
| | - Hendrik A. Zuiderbaan
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
| | - Behrouz Zandieh Doulabi
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Faculty of Oral Cell Biology, Academic Centre of Dentistry Amsterdam, Amsterdam, The Netherlands
| | - Albert J. van der Veen
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands
| | - Peter M. van de Ven
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands
| | - Theo H. Smit
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, VU University Medical Center, Amsterdam, The Netherlands
- Skeletal Tissue Engineering Group Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Marco N. Helder
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, VU University Medical Center, Amsterdam, The Netherlands
- Skeletal Tissue Engineering Group Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Barend J. van Royen
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, VU University Medical Center, Amsterdam, The Netherlands
- Skeletal Tissue Engineering Group Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Margriet G. Mullender
- Department of Orthopedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
- Research institute MOVE, VU University Medical Center, Amsterdam, The Netherlands
- Skeletal Tissue Engineering Group Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
- Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands
- * E-mail:
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Tilwani RK, Bader DL, Chowdhury TT. Biomechanical Conditioning Enhanced Matrix Synthesis in Nucleus Pulposus Cells Cultured in Agarose Constructs with TGFβ. J Funct Biomater 2012; 3:23-36. [PMID: 24956513 PMCID: PMC4031018 DOI: 10.3390/jfb3010023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 12/23/2011] [Accepted: 12/28/2011] [Indexed: 11/24/2022] Open
Abstract
Biomechanical signals play an important role in normal disc metabolism and pathology. For instance, nucleus pulposus (NP) cells will regulate metabolic activities and maintain a balance between the anabolic and catabolic cascades. The former involves factors such as transforming growth factor-β (TGFβ) and mechanical stimuli, both of which are known to regulate matrix production through autocrine and paracrine mechanisms. The present study examined the combined effect of TGFβ and mechanical loading on anabolic activities in NP cells cultured in agarose constructs. Stimulation with TGFβ and dynamic compression reduced nitrite release and increased matrix synthesis and gene expression of aggrecan and collagen type II. The findings from this work has the potential for developing regenerative treatment strategies which could either slow down or stop the degenerative process and/or promote healing mechanisms in the intervertebral disc.
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Affiliation(s)
- Reshma K Tilwani
- School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Dan L Bader
- School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Tina T Chowdhury
- School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
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Chan SCW, Ferguson SJ, Gantenbein-Ritter B. The effects of dynamic loading on the intervertebral disc. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2011; 20:1796-812. [PMID: 21541667 DOI: 10.1007/s00586-011-1827-1] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 03/21/2011] [Accepted: 04/20/2011] [Indexed: 01/08/2023]
Abstract
Loading is important to maintain the balance of matrix turnover in the intervertebral disc (IVD). Daily cyclic diurnal assists in the transport of large soluble factors across the IVD and its surrounding circulation and applies direct and indirect stimulus to disc cells. Acute mechanical injury and accumulated overloading, however, could induce disc degeneration. Recently, there is more information available on how cyclic loading, especially axial compression and hydrostatic pressure, affects IVD cell biology. This review summarises recent studies on the response of the IVD and stem cells to applied cyclic compression and hydrostatic pressure. These studies investigate the possible role of loading in the initiation and progression of disc degeneration as well as quantifying a physiological loading condition for the study of disc degeneration biological therapy. Subsequently, a possible physiological/beneficial loading range is proposed. This physiological/beneficial loading could provide insight into how to design loading regimes in specific system for the testing of various biological therapies such as cell therapy, chemical therapy or tissue engineering constructs to achieve a better final outcome. In addition, the parameter space of 'physiological' loading may also be an important factor for the differentiation of stem cells towards most ideally 'discogenic' cells for tissue engineering purpose.
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Affiliation(s)
- Samantha C W Chan
- ARTORG Center for Biomedical Engineering, Spine Research Center, Institute for Surgical Technology and Biomechanics, University of Bern, Stauffacherstrasse 78, 3014 Bern, Switzerland
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