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Elmounedi N, Keskes H. Establishment of intervertebral disc degeneration models; A review of the currently used models. J Orthop 2024; 56:50-56. [PMID: 38784950 PMCID: PMC11109335 DOI: 10.1016/j.jor.2024.05.020] [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: 04/29/2024] [Accepted: 05/12/2024] [Indexed: 05/25/2024] Open
Abstract
One of the frequent causes of low back pain is intervertebral disc degeneration (IDD), which is followed by discogenic pain. Some significant risk factors that have been linked to the onset and progression of IDD include age, mechanical imbalance, changes in nutrition and inflammation. According to recent studies, five types of animal models are established for producing IDD: the spontaneous models, the puncture models, the biomechanical models, the chemical models and the hybrid models. These models are crucial in studying and understanding IDD's natural history and identifying potential treatment targets for IDD. In our study, we'll talk about the technical aspects of these models, the time between model establishment and the apparition of observable degradation, and their potential in various research. Each animal model should be compared to the human natural IDD pathogenesis to guide future research efforts in this area. By improving knowledge and appropriate application of various animal models, we seek to raise awareness of this illness and further translational research.
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Affiliation(s)
- Najah Elmounedi
- Cell Therapy and Experimental Surgery of Musculoskeletal System LR18SP1 Lab, Faculty of Medicine, Sfax, Tunisia
| | - Hassib Keskes
- Cell Therapy and Experimental Surgery of Musculoskeletal System LR18SP1 Lab, Faculty of Medicine, Sfax, Tunisia
- Department of Orthopedics and Traumatology, CHU Habib Bourguiba, Sfax, Tunisia
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Walk R, Broz K, Jing L, Potter R, Gonzalez CE, Beeve A, Scheller E, Gupta M, Setton L, Tang SY. The progression of neurovascular features and chemokine signatures of the intervertebral disc with degeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.12.603182. [PMID: 39071400 PMCID: PMC11275839 DOI: 10.1101/2024.07.12.603182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Inflammatory cytokine production and de novo neurovascularization have been identified in painful, degenerated intervertebral discs (IVDs). However, the temporal trajectories of these key pathoanatomical features, including the cascade of inflammatory chemokines and neo- vessel and neurite infiltration, and their associations with IVD degeneration, remain relatively unknown. Investigating this process in the caudal mouse IVD enables the opportunity to study the tissue-specific response without confounding inflammatory signaling from neighboring structures. Thus this study aims to define the progression of chemokine production and neurovascular invasion during the IVD degeneration initiated by injury in the caudal spine 3-month-old C57BL6/J mice. Forty-nine IVD-secreted chemokines and matrix metalloproteinases (MMPs) was measured using multiplex ELISA, and the intradiscal infiltrating vessels (endomucin) and nerves (protein-gene-product 9.5) was quantified in the tissue volume using immunohistochemistry. Injury provoked the increase secretion of IL6, CCL2, CCL12, CCL17, CCL20, CCL21, CCL22, CXCL2 and MMP2 proteins. The centrality and structure of inflammatory networks in IVDs evolved over the 12 post-injury weeks, highlighting distinct responses between the acute and chronic phases. Neurites propagated rapidly within 2-weeks post-injury and remained relatively constant until 12-weeks. Vascular vessel length was observed to peak at 4-weeks post-injury and it regressed by 12-weeks. These findings identified the temporal flux of inflammatory chemokines and pain-associated pathoanatomy in a model of IVD degeneration using the mouse caudal spine.
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Mark Kim MK, Lawrence M, Quinonez D, Brooks C, Ramachandran R, Séguin CA. Transient receptor potential vanilloid 4 regulates extracellular matrix composition and mediates load-induced intervertebral disc degeneration in a mouse model. Osteoarthritis Cartilage 2024; 32:881-894. [PMID: 38604493 DOI: 10.1016/j.joca.2024.04.001] [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: 10/18/2023] [Revised: 03/25/2024] [Accepted: 04/02/2024] [Indexed: 04/13/2024]
Abstract
OBJECTIVE Transient receptor potential vanilloid 4 (TRPV4) is a multi-modally activated cation channel that mediates mechanotransduction pathways by which musculoskeletal tissues respond to mechanical load and regulate tissue health. Using conditional Trpv4 knockout mice, we investigated the role of Trpv4 in regulating intervertebral disc (IVD) health and injury-induced IVD degeneration. METHODS Col2-Cre;Trpv4fl/f (Trpv4 KO) mice were used to knockout Trpv4 in all type 2 collagen-expressing cells. Effects of gene targeting alone was assessed in lumbar spines, using vertebral bone length measurement, histological, immunohistochemistry and gene expression analyses, and mechanical testing. Disc puncture was performed on caudal IVDs of wild-type (WT) and Trpv4 KO mice at 2.5- and 6.5-months-of-age. Six weeks after puncture (4- and 8-months-of-age at sacrifice), caudal spines were assessed using histological analyses. RESULTS While loss of Trpv4 did not significantly alter vertebral bone length and tissue histomorphology compared to age-matched WT mice, Trpv4 KO mice showed decreased proteoglycan and PRG4 staining in the annulus fibrosus compared to WT. At the gene level, Trpv4 KO mice showed significantly increased expression of Acan, Bgn, and Prg4 compared to WT. Functionally, loss of Trpv4 was associated with significantly increased neutral zone length in lumbar IVDs. Following puncture, both Trpv4 KO and WT mice showed similar signs of degeneration at the site of injury. Interestingly, loss of Trpv4 prevented mechanically-induced degeneration in IVDs adjacent to sites of injury. CONCLUSION These studies suggest a role for Trpv4 in regulating extracellular matrix synthesis and mediating the response of IVD tissues to mechanical stress.
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Affiliation(s)
- Min Kyu Mark Kim
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Matthew Lawrence
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Diana Quinonez
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Courtney Brooks
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Cheryle A Séguin
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
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Tang SN, Salazar-Puerta AI, Heimann MK, Kuchynsky K, Rincon-Benavides MA, Kordowski M, Gunsch G, Bodine L, Diop K, Gantt C, Khan S, Bratasz A, Kokiko-Cochran O, Fitzgerald J, Laudier DM, Hoyland JA, Walter BA, Higuita-Castro N, Purmessur D. Engineered extracellular vesicle-based gene therapy for the treatment of discogenic back pain. Biomaterials 2024; 308:122562. [PMID: 38583365 PMCID: PMC11164054 DOI: 10.1016/j.biomaterials.2024.122562] [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: 08/22/2023] [Revised: 02/23/2024] [Accepted: 03/31/2024] [Indexed: 04/09/2024]
Abstract
Painful musculoskeletal disorders such as intervertebral disc (IVD) degeneration associated with chronic low back pain (termed "Discogenic back pain", DBP), are a significant socio-economic burden worldwide and contribute to the growing opioid crisis. Yet there are very few if any successful interventions that can restore the tissue's structure and function while also addressing the symptomatic pain. Here we have developed a novel non-viral gene therapy, using engineered extracellular vesicles (eEVs) to deliver the developmental transcription factor FOXF1 to the degenerated IVD in an in vivo model. Injured IVDs treated with eEVs loaded with FOXF1 demonstrated robust sex-specific reductions in pain behaviors compared to control groups. Furthermore, significant restoration of IVD structure and function in animals treated with FOXF1 eEVs were observed, with significant increases in disc height, tissue hydration, proteoglycan content, and mechanical properties. This is the first study to successfully restore tissue function while modulating pain behaviors in an animal model of DBP using eEV-based non-viral delivery of transcription factor genes. Such a strategy can be readily translated to other painful musculoskeletal disorders.
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Affiliation(s)
- Shirley N Tang
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | - Ana I Salazar-Puerta
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | - Mary K Heimann
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | - Kyle Kuchynsky
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | | | - Mia Kordowski
- Biophysics Graduate Program, The Ohio State University, USA
| | - Gilian Gunsch
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | - Lucy Bodine
- Department of Mechanical Engineering, College of Engineering, The Ohio State University, USA
| | - Khady Diop
- Department of Biology, College of Arts and Sciences, The Ohio State University, USA
| | - Connor Gantt
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA
| | - Safdar Khan
- Department of Orthopedics, The Ohio State University Wexner Medical Center, USA
| | - Anna Bratasz
- Small Animal Imaging Center Shared Resources, Wexner Medical Center, USA
| | - Olga Kokiko-Cochran
- Department of Neuroscience, The Ohio State University, USA; Institute for Behavioral Medicine Research, Neurological Institute, The Ohio State University, USA
| | - Julie Fitzgerald
- Department of Neuroscience, The Ohio State University, USA; Institute for Behavioral Medicine Research, Neurological Institute, The Ohio State University, USA
| | - Damien M Laudier
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, USA
| | - Judith A Hoyland
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, The University of Manchester, Manchester, UK; NIHR Manchester Musculoskeletal Biomedical Research Centre, Manchester University, NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Benjamin A Walter
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA; Department of Orthopedics, The Ohio State University Wexner Medical Center, USA
| | - Natalia Higuita-Castro
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA; Biophysics Graduate Program, The Ohio State University, USA; Department of Neurosurgery, The Ohio State University, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, USA.
| | - Devina Purmessur
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, USA; Department of Orthopedics, The Ohio State University Wexner Medical Center, USA.
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Lim J, Huang SS, Nikkhoo M, Tai WT, Chu YC, Chien A, Wang JL. ASIC3 roles in mechanosensitive elongation of nucleus pulposus cells. J Biomech 2024; 163:111938. [PMID: 38217980 DOI: 10.1016/j.jbiomech.2024.111938] [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: 03/08/2023] [Revised: 12/14/2023] [Accepted: 01/04/2024] [Indexed: 01/15/2024]
Abstract
Morphological changes of the nucleus pulposus (NP) cells occur concomitantly as part of the intervertebral disc (IVD) degeneration and excessive mechanical loading has been speculated as a significant key factor for contributing to such morphological changes. Therefore, we hypothesize that stress exerted on NP cells can cause a deformity of nucleus in response. The changes of cell morphology is observed in degenerative nucleus pulposus. One of the reasons for degeneration of NP is due to overloading of NP especially in the obese population. So the nucleus deformity caused by stress/force is of our study interest. To delineate the effects and role of mechanical stress, we developed a 3D assay using hydrogel cultures with a circular hole generated with needle indentation to simulate a local stress concentration along the edge of the hole. A stressed zone, encompassing 100 μm of range from the circular edge, is defined based on stress concentration calculation to enable quantitative analysis against the control zone. Our results demonstrated that the circular hole produces stress-induced morphological changes in NP cells. The tangential elongation of NP cells and their nucleus shape changes in the stressed zone are significantly increased compared to the non-stressed control zone. It is proposed that the cell elongation is a direct response to elevated stress within the stressed zone. Subsequently we found the stress induced morphological changes of the NP cells can be significantly reduced by inhibiting ASIC3. This suggests ASIC3 plays an important role of play in mechano-signaling of NP cells.
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Affiliation(s)
- Jormay Lim
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan
| | - Shao-Shiang Huang
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan
| | - Mohammad Nikkhoo
- Graduate Institute of Rehabilitation Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Wei-Ting Tai
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan
| | - Ya-Cherng Chu
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan; Center of Medical Devices, National Taiwan University, Taipei, Taiwan
| | - Andy Chien
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan
| | - Jaw-Lin Wang
- Department of Biomedical Engineering, College of Medicine and College of Engineering, Nation Taiwan University, Taipei, Taiwan; Center of Medical Devices, National Taiwan University, Taipei, Taiwan.
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Muir VG, Fainor M, Orozco BS, Hilliard RL, Boyes M, Smith HE, Mauck RL, Schaer TP, Burdick JA, Gullbrand SE. Injectable Radiopaque Hyaluronic Acid Granular Hydrogels for Intervertebral Disc Repair. Adv Healthc Mater 2023:e2303326. [PMID: 38142300 PMCID: PMC11193841 DOI: 10.1002/adhm.202303326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/10/2023] [Indexed: 12/25/2023]
Abstract
Injectable hydrogels offer minimally-invasive treatment options for degenerative disc disease, a prevalent condition affecting millions annually. Many hydrogels explored for intervertebral disc (IVD) repair suffer from weak mechanical integrity, migration issues, and expulsion. To overcome these limitations, an injectable and radiopaque hyaluronic acid granular hydrogel is developed. The granular structure provides easy injectability and low extrusion forces, while the radiopacity enables direct visualization during injection into the disc and non-invasive monitoring after injection. The radiopaque granular hydrogel is injected into rabbit disc explants to investigate restoration of healthy disc mechanics following needle puncture injury ex vivo and then delivered in a minimally-invasive manner into the intradiscal space in a clinically-relevant in vivo large animal goat model of IVD degeneration initiated through degradation by chondroitinase. The radiopaque granular hydrogel successfully halted loss of disc height due to degeneration. Further, the hydrogel not only enhanced proteoglycan content and reduced collagen content in the nucleus pulposus (NP) region compared to degenerative discs, but also helped to maintain the structural integrity of the disc and promote healthy segregation of the NP and annulus fibrosus regions. Overall, this study demonstrates the great potential of an injectable radiopaque granular hydrogel for treatment of degenerative disc disease.
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Affiliation(s)
- Victoria G Muir
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Matthew Fainor
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, 19104, USA
| | - Brianna S Orozco
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, 19104, USA
| | - Rachel L Hilliard
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Madeline Boyes
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Harvey E Smith
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, 19104, USA
| | - Robert L Mauck
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, 19104, USA
| | - Thomas P Schaer
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Jason A Burdick
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, 80303, USA
- Department of Chemical and Biological Engineering, College of Engineering and Applied Science, University of Colorado Boulder, Boulder, CO, 80303, USA
| | - Sarah E Gullbrand
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, 19104, USA
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7
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Fainor M, Orozco BS, Muir VG, Mahindroo S, Gupta S, Mauck RL, Burdick JA, Smith HE, Gullbrand SE. Mechanical crosstalk between the intervertebral disc, facet joints, and vertebral endplate following acute disc injury in a rabbit model. JOR Spine 2023; 6:e1287. [PMID: 38156057 PMCID: PMC10751980 DOI: 10.1002/jsp2.1287] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/21/2023] [Accepted: 09/06/2023] [Indexed: 12/30/2023] Open
Abstract
Background Vertebral endplate sclerosis and facet osteoarthritis have been documented in animals and humans. However, it is unclear how these adjacent pathologies engage in crosstalk with the intervertebral disc. This study sought to elucidate this crosstalk by assessing each compartment individually in response to acute disc injury. Methods Eleven New Zealand White rabbits underwent annular disc puncture using a 16G or 21G needle. At 4 and 10 weeks, individual compartments of the motion segment were analyzed. Discs underwent T 1 relaxation mapping with MRI contrast agent gadodiamide as well T 2 mapping. Both discs and facets underwent mechanical testing via vertebra-disc-vertebra tension-compression creep testing and indentation testing, respectively. Endplate bone density was quantified via μCT. Discs and facets were sectioned and stained for histology scoring. Results Intervertebral discs became more degenerative with increasing needle diameter and time post-puncture. Bone density also increased in endplates adjacent to both 21G and 16G punctured discs leading to reduced gadodiamide transport at 10 weeks. The facet joints, however, did not follow this same trend. Facets adjacent to 16G punctured discs were less degenerative than facets adjacent to 21G punctured discs at 10 weeks. 16G facets were more degenerative at 4 weeks than at 10, suggesting the cartilage had recovered. The formation of severe disc osteophytes in 16G punctured discs between 4 and 10 weeks likely offloaded the facet cartilage, leading to the recovery observed. Conclusions Overall, this study supports that degeneration spans the whole spinal motion segment following disc injury. Vertebral endplate thickening occurred in response to disc injury, which limited the diffusion of small molecules into the disc. This work also suggests that altered disc mechanics can induce facet degeneration, and that extreme bony remodeling adjacent to the disc may promote facet cartilage recovery through offloading of the articular cartilage.
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Affiliation(s)
- Matthew Fainor
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
| | - Brianna S. Orozco
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
| | - Victoria G. Muir
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Sonal Mahindroo
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
- Department of BiologySt. Bonaventure UniversitySt. BonaventureNew YorkUSA
| | - Sachin Gupta
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
| | - Robert L. Mauck
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Jason A. Burdick
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- BioFrontiers Institute and Department of Chemical and Biological EngineeringUniversity of Colorado BoulderBoulderColoradoUSA
| | - Harvey E. Smith
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
| | - Sarah E. Gullbrand
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
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8
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Xiao F, van Dieën JH, Han J, Maas H. Stab lesion of the L4/L5 intervertebral disc in the rat causes acute changes in disc bending mechanics. J Biomech 2023; 161:111830. [PMID: 37821333 DOI: 10.1016/j.jbiomech.2023.111830] [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: 04/06/2023] [Revised: 10/03/2023] [Accepted: 10/05/2023] [Indexed: 10/13/2023]
Abstract
Low-back pain often coincides with altered neuromuscular control, possibly due to changes in spine stability resulting from injury or degeneration, or due to effects of nociception. The relative importance of these mechanisms, and their possible interaction, are unknown. In spine bending, the bulk of the load is borne by the IVD, yet the acute effects of intervertebral disc (IVD) injury on bending mechanics have not been investigated. In the present study, we aimed to quantify the acute effects of a stab lesion of the disc on its mechanical properties, because such changes can be expected to elicit compensatory changes in neuromuscular control. L4/L5 spinal segments were collected from 27 Wistar rats within two hours after sacrifice and stored at -20℃. Following thawing, bending tests were performed to assess the intersegmental angle-moment characteristics. Specimens were loaded in right bending, left bending and flexion, before and after a stab lesion of the IVD fully penetrating the nucleus pulposus. In the angle-moment curves, we found reduced moments at equal bending angles after IVD lesion in left bending, right bending and flexion. Peak stiffness, peak moment, and hysteresis were significantly decreased (by 7.8-27.7 %) after IVD lesion in all directions. In conclusion, L4/L5 IVD lesion in the rat caused small to moderate acute changes in IVD mechanical properties. Our next steps will be to evaluate the longer term effects of IVD lesion on spine mechanics and the neural control of trunk muscles.
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Affiliation(s)
- Fangxin Xiao
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands; School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Jaap H van Dieën
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Jia Han
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai, China; Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Huub Maas
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands.
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9
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Peredo AP, Gullbrand SE, Friday CS, Orozco BS, Dehghani B, Jenk AC, Bonnevie ED, Hilliard RL, Zlotnick HM, Dodge GR, Lee D, Engiles JB, Hast MW, Schaer TP, Smith HE, Mauck RL. Tension-activated nanofiber patches delivering an anti-inflammatory drug improve repair in a goat intervertebral disc herniation model. Sci Transl Med 2023; 15:eadf1690. [PMID: 37967202 PMCID: PMC10812087 DOI: 10.1126/scitranslmed.adf1690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 10/26/2023] [Indexed: 11/17/2023]
Abstract
Conventional microdiscectomy treatment for intervertebral disc herniation alleviates pain but does not repair the annulus fibrosus, resulting in a high incidence of recurrent herniation and persistent dysfunction. The lack of repair and the acute inflammation that arise after injury can further compromise the disc and result in disc-wide degeneration in the long term. To address this clinical need, we developed tension-activated repair patches (TARPs) for annulus fibrosus repair and local delivery of the anti-inflammatory factor anakinra (a recombinant interleukin-1 receptor antagonist). TARPs transmit physiologic strain to mechanically activated microcapsules embedded within the patch, which release encapsulated bioactive molecules in direct response to spinal loading. Mechanically activated microcapsules carrying anakinra were loaded into TARPs, and the effects of TARP-mediated annular repair and anakinra delivery were evaluated in a goat model of annular injury in the cervical spine. TARPs integrated with native tissue and provided structural reinforcement at the injury site that prevented aberrant disc-wide remodeling resulting from detensioning of the annular fibrosus. The delivery of anakinra by TARP implantation increased matrix deposition and retention at the injury site and improved maintenance of disc extracellular matrix. Anakinra delivery additionally attenuated the inflammatory response associated with TARP implantation, decreasing osteolysis in adjacent vertebrae and preserving disc cellularity and matrix organization throughout the annulus fibrosus. These results demonstrate the therapeutic potential of TARPs for the treatment of intervertebral disc herniation.
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Affiliation(s)
- Ana P. Peredo
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Sarah E. Gullbrand
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Chet S. Friday
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
| | - Briana S. Orozco
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Bijan Dehghani
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Austin C. Jenk
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Edward D. Bonnevie
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Rachel L. Hilliard
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania; Philadelphia, PA 19348, USA
| | - Hannah M. Zlotnick
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - George R. Dodge
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania; Philadelphia, 19104, USA
| | - Julie B. Engiles
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania; Philadelphia, PA 19348, USA
- Department of Pathobiology, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania; Philadelphia, PA 19348, USA
| | - Michael W. Hast
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Thomas P. Schaer
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania; Philadelphia, PA 19348, USA
| | - Harvey E. Smith
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
| | - Robert L. Mauck
- Department of Bioengineering, University of Pennsylvania; Philadelphia, 19104, USA
- Department of Orthopaedic Surgery, University of Pennsylvania; Philadelphia, 19104, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center; Philadelphia, 19104, USA
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10
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Zou X, Zhang X, Han S, Wei L, Zheng Z, Wang Y, Xin J, Zhang S. Pathogenesis and therapeutic implications of matrix metalloproteinases in intervertebral disc degeneration: A comprehensive review. Biochimie 2023; 214:27-48. [PMID: 37268183 DOI: 10.1016/j.biochi.2023.05.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 05/22/2023] [Accepted: 05/22/2023] [Indexed: 06/04/2023]
Abstract
Intervertebral disc (IVD) degeneration (IDD) is a common disorder that affects the spine and is a major cause of lower back pain (LBP). The extracellular matrix (ECM) is the structural foundation of the biomechanical properties of IVD, and its degradation is the main pathological characteristic of IDD. Matrix metalloproteinases (MMPs) are a group of endopeptidases that play an important role in the degradation and remodeling of the ECM. Several recent studies have shown that the expression and activity of many MMP subgroups are significantly upregulated in degenerated IVD tissue. This upregulation of MMPs results in an imbalance of ECM anabolism and catabolism, leading to the degradation of the ECM and the development of IDD. Therefore, the regulation of MMP expression is a potential therapeutic target for the treatment of IDD. Recent research has focused on identifying the mechanisms by which MMPs cause ECM degradation and promote IDD, as well as on developing therapies that target MMPs. In summary, MMP dysregulation is a crucial factor in the development of IDD, and a deeper understanding of the mechanisms involved is needed to develop effective biological therapies that target MMPs to treat IDD.
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Affiliation(s)
- Xiaosong Zou
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Xingmin Zhang
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Song Han
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Lin Wei
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Zhi Zheng
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Yongjie Wang
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Jingguo Xin
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China
| | - Shaokun Zhang
- Department of Spinal Surgery, The First Hospital of Jilin University, Changchun, 130021, China; Jilin Engineering Research Center for Spine and Spinal Cord Injury, Changchun, 130021, China.
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11
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miR-4478 Accelerates Nucleus Pulposus Cells Apoptosis Induced by Oxidative Stress by Targeting MTH1. Spine (Phila Pa 1976) 2023; 48:E54-E69. [PMID: 36130054 PMCID: PMC9897280 DOI: 10.1097/brs.0000000000004486] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 08/31/2022] [Indexed: 02/01/2023]
Abstract
OBJECTIVES Low back pain is the leading cause of disability in the elderly population and is strongly associated with intervertebral disk degeneration (IVDD). However, the precise molecular mechanisms regulating IVDD remain elusive. This study aimed to investigate the role of differentially expressed miRNAs in the pathogenesis of IVDD. MATERIALS AND METHODS We analyzed miRNA microarray datasets to identify differentially expressed miRNAs in IVDD progression and conducted quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analysis to further confirm the differential expression of miR-4478 in nucleus pulposus (NP) tissues of patients diagnosed with IVDD. Using public databases of miRNA-mRNA interactions, we predicted the target genes of miR-4478, and subsequent flow cytometry and western blot analyses demonstrated the effect of MTH1 in H 2 O 2 -induced nucleus pulposus cells (NPCs) apoptosis. Finally, miR-4478 inhibitor was injected into NP tissues of the IVDD mouse model to explore the effect of miR-4478 in vivo. RESULTS miR-4478 was upregulated in NP tissues from IVDD patients. Silencing of miR-4478 inhibits H 2 O 2 -induced NPCs apoptosis. MTH1 was identified as a target gene for miR-4478, and miR-4478 regulates H 2 O 2 -induced NPCs apoptosis by modulating MTH1. In addition, downregulation of miR-4478 alleviated IVDD in a mouse model. CONCLUSIONS In summary, our study provides evidence that miR-4478 may aggravate IVDD through its target gene MTH1 by accelerating oxidative stress in NPCs and demonstrates that miR-4478 has therapeutic potential in IVDD treatment.
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Gupta S, Xiao R, Fainor M, Mauck RL, Smith HE, Gullbrand SE. Level dependent alterations in human facet cartilage mechanics and bone morphometry with spine degeneration. J Orthop Res 2023; 41:674-683. [PMID: 35770853 PMCID: PMC9800647 DOI: 10.1002/jor.25407] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 06/10/2022] [Accepted: 06/24/2022] [Indexed: 02/04/2023]
Abstract
The zygapophyseal joints of the spine, also known as the facet joints, are paired diarthrodial joints posterior to the intervertebral disc and neural elements. The pathophysiology of facet osteoarthritis (OA), as well as crosstalk between the disc and facets, remains largely understudied compared to disc degeneration. The purpose of this study was to characterize alterations to human facet cartilage and subchondral bone across a spectrum of degeneration and to investigate correlations between disc and facet degeneration. Human lumbar facet articular surfaces from six independent donors were subject to creep indentation mechanical testing to quantify cartilage mechanical properties, followed by microcomputed tomography (µCT) analyses for subchondral bone morphometry. The degenerative state of each articular surface was assessed via macroscopic scoring and via Osteoarthritis Research Society International histopathology scoring. Our data suggest reduced facet cartilage compressive and tensile moduli and increased permeability with increasing degenerative grade, particularly at the lower levels of the spine. µCT analyses revealed spinal level-dependent alterations to the subchondral bone, with an increase in trabecular bone at the L4-L5 level, but a decrease at the upper levels of the lumbar spine with increasing degenerative grade. Cortical bone volume fraction was generally decreased with increasing degenerative grade across spinal levels. Correlation analysis revealed several associations between quantitative measures of disc degeneration and facet OA. This study showed that alterations in the mechanical properties of facet cartilage and in the structural properties of facet subchondral bone correlated with aspects of disc degeneration and were highly dependent on spinal level.
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Affiliation(s)
- Sachin Gupta
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Rui Xiao
- Department of Biostatistics, Epidemiology & Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Matthew Fainor
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Robert L. Mauck
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA
| | - Harvey E. Smith
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Sarah E. Gullbrand
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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13
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pH-Responsive Delivery of H2 through Ammonia Borane-Loaded Hollow Polydopamine for Intervertebral Disc Degeneration Therapy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2023; 2023:7773609. [PMID: 36778204 PMCID: PMC9911255 DOI: 10.1155/2023/7773609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 11/29/2022] [Accepted: 12/21/2022] [Indexed: 02/05/2023]
Abstract
An imbalance in oxidative and inflammatory regulation is the main contributor to intervertebral disc degeneration (IDD). Hydrogen (H2) therapy is a promising antioxidation and anti-inflammatory approach. However, the key to the treatment is how to maintain the long-term effective H2 concentration in the intervertebral disc (IVD). Therefore, we developed a pH-responsive delivery of H2 through ammonia borane-loaded hollow polydopamine (AB@HPDA) for IDD therapy, which has sufficient capacity to control long-term H2 release in an acid-dependent manner in degenerative IVD. The characterization, toxicity, and pH-responsive H2 release of AB@HPDA was detected in vitro. The metabolization of AB@HPDA in the degenerated IVD was tested by in vivo imaging. The therapeutic effect of AB@HPDA on IDD was tested in vivo by X-ray, MRI, water content of the disc, and histological changes. Nuclear extracellular matrix (ECM) components, oxidative stress, and inflammation were also tested to explore potential therapeutic mechanisms. AB@HPDA has good biocompatibility at concentrations less than 500 μg/mL. The H2 release of AB@HPDA was pH responsive. Therefore, AB@HPDAs can provide efficient hydrogen therapy with controlled H2 release in response to the acidic degenerated IVD microenvironment. The metabolization of AB@HPDA in IVD was slow and lasted up to 11 days. HPDA and AB@HPDA significantly inhibited IDD, as tested by X-ray, MRI, disc water content, and histology (P < 0.05). pH-responsive H2 delivery through AB@HPDAs has the potential to efficiently treat IDD by inhibiting ECM degradation and rebalancing oxidative stress and inflammation in degenerative IVDs.
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Alini M, Diwan AD, Erwin WM, Little CB, Melrose J. An update on animal models of intervertebral disc degeneration and low back pain: Exploring the potential of artificial intelligence to improve research analysis and development of prospective therapeutics. JOR Spine 2023; 6:e1230. [PMID: 36994457 PMCID: PMC10041392 DOI: 10.1002/jsp2.1230] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 08/31/2022] [Accepted: 09/11/2022] [Indexed: 02/03/2023] Open
Abstract
Animal models have been invaluable in the identification of molecular events occurring in and contributing to intervertebral disc (IVD) degeneration and important therapeutic targets have been identified. Some outstanding animal models (murine, ovine, chondrodystrophoid canine) have been identified with their own strengths and weaknesses. The llama/alpaca, horse and kangaroo have emerged as new large species for IVD studies, and only time will tell if they will surpass the utility of existing models. The complexity of IVD degeneration poses difficulties in the selection of the most appropriate molecular target of many potential candidates, to focus on in the formulation of strategies to effect disc repair and regeneration. It may well be that many therapeutic objectives should be targeted simultaneously to effect a favorable outcome in human IVD degeneration. Use of animal models in isolation will not allow resolution of this complex issue and a paradigm shift and adoption of new methodologies is required to provide the next step forward in the determination of an effective repairative strategy for the IVD. AI has improved the accuracy and assessment of spinal imaging supporting clinical diagnostics and research efforts to better understand IVD degeneration and its treatment. Implementation of AI in the evaluation of histology data has improved the usefulness of a popular murine IVD model and could also be used in an ovine histopathological grading scheme that has been used to quantify degenerative IVD changes and stem cell mediated regeneration. These models are also attractive candidates for the evaluation of novel anti-oxidant compounds that counter inflammatory conditions in degenerate IVDs and promote IVD regeneration. Some of these compounds also have pain-relieving properties. AI has facilitated development of facial recognition pain assessment in animal IVD models offering the possibility of correlating the potential pain alleviating properties of some of these compounds with IVD regeneration.
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Affiliation(s)
- Mauro Alini
- AO Research Institute Davos Platz Switzerland
| | - Ashish D. Diwan
- Spine Service, Department of Orthopedic Surgery, St. George & Sutherland Campus, Clinical School University of New South Wales Sydney New South Wales Australia
| | - W. Mark Erwin
- Department of Surgery University of Toronto Ontario Canada
| | - Chirstopher B. Little
- Raymond Purves Bone and Joint Research Laboratory Kolling Institute, Sydney University Faculty of Medicine and Health, Northern Sydney Area Health District, Royal North Shore Hospital St. Leonards New South Wales Australia
| | - James Melrose
- Raymond Purves Bone and Joint Research Laboratory Kolling Institute, Sydney University Faculty of Medicine and Health, Northern Sydney Area Health District, Royal North Shore Hospital St. Leonards New South Wales Australia
- Graduate School of Biomedical Engineering The University of New South Wales Sydney New South Wales Australia
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15
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Song XX, Jin LY, Li Q, Li XF, Luo Y. Estrogen receptor β/substance P signaling in spinal cord mediates antinociceptive effect in a mouse model of discogenic low back pain. Front Cell Neurosci 2023; 16:1071012. [PMID: 36756381 PMCID: PMC9899865 DOI: 10.3389/fncel.2022.1071012] [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: 10/15/2022] [Accepted: 12/29/2022] [Indexed: 01/24/2023] Open
Abstract
Introduction Discogenic low back pain (DLBP) is the most commonly described form of back pain. Our previous studies indicated that estrogen-dependent DLBP mechanism was mediated by estrogen receptors (ERs) in the intervertebral disc (IVD) tissue, and the IVD degeneration degree is accompanied by downregulation of ERs, particularly ERβ. However, the neuropathological mechanisms underlying ERs modulation of DLBP are still not well understood. In this study, we investigated the antinociceptive effects of selective ERβ agonists on DLBP-related behavior by regulating substance P in spinal cord and dorsal root ganglia. Methods Two weeks after ovariectomies, 18-week-old female mice were randomly separated into four groups: control group; DLBP sham surgery plus vehicle group; DLBP plus vehicle group; DLBP plus ERβ-specific agonist diarylpropionitrile (DPN) group. Behavioral data was collected including behavioral measures of axial back pain (grip force and tail suspension tests) and radiating hypersensitivity (mechanical sensitivity and cold sensitivity test). Dual label scanning confocal immunofluorescence microscopy was used to observe spatial colocalization of ERβ and substance P in spinal cord. Substance P changes in spinal cord and dorsal root ganglia were measured by immunohistochemistry and real-time PCR. Results ERβ activation could improve both axial and radiating behavioral disorders of DLBP. DPN facilitated the decrease of the amount of time in immobility 1 week after agonist administration. At the time point of 3 weeks, DPN group spent significantly less time in immobility than the vehicle group. In the grip strength tests, starting from postoperative week 1-week 3, DPN injection DLBP mice showed more resistance to stretch than the vehicle injection DLBP mice. Significant differences of cold withdrawal latency time were observed between the DLBP plus DPN injection and DLBP vehicle injection groups at 2- and 3-week injection time point. DPN significantly reversed the paw withdrawal threshold of DLBP mice at the time point of 1, 2, and 3 weeks. Substance P colocalized with ERβ in spinal dorsal horn, mainly in laminae I and II, a connection site of pain transmission. Substance P levels in dorsal horn and dorsal root ganglia of DLBP group were distinctly increased compared with that of control and DLBP sham group. DPN therapy could decrease substance P content in the dorsal horn and the dorsal root ganglia of DLBP mice compared with that of vehicle-treated DLBP mice. Discussion Activation of ERβ is antinociceptive in the DLBP model by controlling substance P in spinal cord and dorsal root ganglia, which might provide a therapeutic target to manage DLBP in the clinic.
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Affiliation(s)
- Xiao-Xing Song
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lin-Yu Jin
- Department of Orthopedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qiang Li
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xin-Feng Li
- Department of Orthopedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,*Correspondence: Xin-Feng Li,
| | - Yan Luo
- Department of Anesthesiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,Yan Luo,
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Zhang L, Du G, Teng B, Shi X, He X, Li N, Chen Y, Xu R. Vascular anatomy-based localization of intervertebral discs assisting needle puncture for constructing a mouse model of mechanical injury-induced lumbar intervertebral disc degeneration. Biochem Biophys Res Commun 2022; 634:196-202. [DOI: 10.1016/j.bbrc.2022.10.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 09/19/2022] [Accepted: 10/05/2022] [Indexed: 11/29/2022]
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He S, Zhou X, Yang G, Zhou Z, Zhang Y, Shao X, Liang T, Lv N, Chen J, Qian Z. Proteomic comparison between physiological degeneration and needle puncture model of disc generation disease. 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 2022; 31:2920-2934. [PMID: 35842490 DOI: 10.1007/s00586-022-07284-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 04/20/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The completeness of the intervertebral disc proteome is fundamental to the integrity and functionality of the intervertebral disc. METHODS The 20 experimental rats were placed into two groups randomly, normal group (NG) and acupuncture pathological degeneration group-2 weeks (APDG-2w). The ten 24-month-old rats were grouped into physiological degeneration group (PDG). Magnetic resonance imaging, X-ray examination, histological staining (hematoxylin & eosin, safranin-O cartilage, and alcian blue staining), and immunohistochemical examination were carried out for assessing the degree of disc degradation. Intervertebral disc was collected, and protein composition was determined by LC- MS, followed by bioinformatic analysis including significance analysis, subcellular localization prediction, protein domain prediction, GO function and KEGG pathway analysis, and protein interaction network construction. LC-PRM was done for protein quantification. RESULTS Physiological degeneration and especially needle puncture decreased T2 signal intensity and intervertebral disc height. Results from hematoxylin & eosin, safranin-O, and alcian blue staining revealed that the annulus fibrosus apparently showed the wavy and collapsed fibrocartilage lamellas in APDG-2w and PDG groups. The contents of the nucleus pulposus were decreased in physiological degeneration group and APDG-2w group compared with NG. Results from immunohistochemical analysis suggested the degeneration of intervertebral disc and inflammation in APDG-2w and PDG groups. The protein composition and expression between needle puncture rat models and the physiological degeneration group showed significant difference. CONCLUSIONS Our studies produced point-reference datasets of normal rats, physiological degeneration rats, and needle puncture rat models, which is beneficial to subsequent pathological studies. There is differential expression of protein expression in degenerative discs with aging and acupuncture, which may be used as a potential discriminating index for different intervertebral degenerations.
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Affiliation(s)
- Shuangjun He
- Department of Orthopedic Surgery, Affiliated Danyang Hospital of Nantong University, The People's Hospital of Danyang, Xinmin Road 2, Danyang, Zhenjiang, 212300, Jiangsu, China
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Xinfeng Zhou
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Guotao Yang
- Department of Orthopedic Surgery, Affiliated Danyang Hospital of Nantong University, The People's Hospital of Danyang, Xinmin Road 2, Danyang, Zhenjiang, 212300, Jiangsu, China
| | - Zhangzhe Zhou
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Yijian Zhang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Xiaofeng Shao
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Ting Liang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China
| | - Nanning Lv
- Department of Orthopedic Surgery, The Second People's Hospital of Lianyungang, 41 Hailian Street, Lianyungang, Jiangsu, China.
| | - Jianhong Chen
- Department of Orthopedic Surgery, Affiliated Danyang Hospital of Nantong University, The People's Hospital of Danyang, Xinmin Road 2, Danyang, Zhenjiang, 212300, Jiangsu, China.
| | - Zhonglai Qian
- Department of Orthopedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, 215006, Jiangsu, China.
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18
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Wang W, Xiao B, Yu L, Wang H, Qi J, Xi Y, Deng G, Gu X, Xu G. Effect of species, concentration and volume of local anesthetics on intervertebral disk degeneration in rats with discoblock. 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 2022; 31:2960-2971. [PMID: 36152221 DOI: 10.1007/s00586-022-07398-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/26/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
PURPOSE Discoblock is effective in relieving discogenic low back pain, but it can also cause intervertebral disk degeneration (IDD). The effect of species, concentration and volume of local anesthetics on IDD with discoblock have not been reported. The purpose was to study the effect of species, concentration and volume of local anesthetics on IDD in rats undergoing discoblock. METHODS The effects of local anesthetics on nucleus pulposus cell (NPC) viability in vitro were studied. NPCs were exposed to lidocaine, bupivacaine and ropivacaine at different concentrations. NPC viability was measured. The least cytotoxic local anesthetic was used in vivo. The concentration and volume of local anesthetics on IDD in rat with discoblocks were tested in vivo. Detection indicators included X-ray, MRI, water content of the disk and histological changes. RESULTS The toxicity of local anesthetics to NPCs was dose and time dependent, and the cytotoxicity of different local anesthetics was different. Among the three local anesthetics, ropivacaine was the least toxic to NPCs. The effect of ropivacaine concentration on IDD was not significant, as detected by X-ray, MRI, disk water content and histology (P < 0.05). The volume of ropivacaine has a significant effect on IDD, as supported by X-ray, MRI, disk water content and histology (P < 0.05). Acupuncture itself significantly increased IDD, as detected by MRI, disk water content and histology (P < 0.05). CONCLUSION Ropivacaine should be selected for its low cytotoxicity. A lower volume and slow injection speed should be used to reduce IDD during discoblock.
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Affiliation(s)
- Weiheng Wang
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China.
| | - Bing Xiao
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China
| | - Lei Yu
- Department of Orthopaedics, The 73Rd Group Army Hospital of PLA, NO.94-96 Wenyuan Road, Xiamen, People's Republic of China
| | - Haotian Wang
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China
| | - Junqiang Qi
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China
| | - Yanhai Xi
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China
| | - Guoying Deng
- Trauma Center, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, 650 Xin Songjiang Road, NO, Shanghai, People's Republic of China
| | - Xin Gu
- Department of Orthopaedics, Tongren Hospital, Shanghai Jiaotong University, No. 1111, Xianxia Road, Shanghai, People's Republic of China
| | - Guohua Xu
- Department of Orthopaedics, Second Affiliated Hospital of Naval Medical University, NO.415 Fengyang Road, Shanghai, People's Republic of China
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Barcellona MN, McDonnell EE, Samuel S, Buckley CT. Rat tail models for the assessment of injectable nucleus pulposus regeneration strategies. JOR Spine 2022; 5:e1216. [PMID: 36203865 PMCID: PMC9520766 DOI: 10.1002/jsp2.1216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/20/2022] [Accepted: 06/26/2022] [Indexed: 11/12/2022] Open
Abstract
Back pain is a global epidemiological and socioeconomic problem often associated with intervertebral disc degeneration; a condition believed to initiate in the nucleus pulposus (NP). There is considerable interest in developing early therapeutic interventions to target the NP and halt degeneration. Rat caudal models of disc degeneration have demonstrated significant utility in the study of disease progression and its impact on tissue structure, composition, and mechanical performance. One significant advantage of the caudal model is the ease of access and high throughput nature. However, considerable variability exists across the literature in terms of experimental setup and parameters. The objective of this article is to aid researchers in the design and development of caudal puncture models by providing details and insight into the most reported experimental parameters. Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were employed to screen the existing literature and 80 manuscripts met the inclusion criteria. Disc geometry, surgical approaches, effect of needle gauge size to induce degeneration, therapeutic volume, outcome measures, and associated limitations are considered and discussed, and a range of recommendations based on different research questions are presented.
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Affiliation(s)
- Marcos N. Barcellona
- Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin The University of Dublin Dublin Ireland
- Discipline of Mechanical, Manufacturing and Biomedical Engineering, School of Engineering, Trinity College Dublin The University of Dublin Dublin Ireland
| | - Emily E. McDonnell
- Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin The University of Dublin Dublin Ireland
- Discipline of Mechanical, Manufacturing and Biomedical Engineering, School of Engineering, Trinity College Dublin The University of Dublin Dublin Ireland
| | - Shani Samuel
- Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin The University of Dublin Dublin Ireland
- Discipline of Mechanical, Manufacturing and Biomedical Engineering, School of Engineering, Trinity College Dublin The University of Dublin Dublin Ireland
| | - Conor T. Buckley
- Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin The University of Dublin Dublin Ireland
- Discipline of Mechanical, Manufacturing and Biomedical Engineering, School of Engineering, Trinity College Dublin The University of Dublin Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre, Royal College of Surgeons in Ireland & Trinity College Dublin The University of Dublin Dublin Ireland
- Tissue Engineering Research Group, Department of Anatomy and Regenerative Medicine Royal College of Surgeons in Ireland Dublin 2 Ireland
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20
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Panebianco CJ, Rao S, Hom WW, Meyers JH, Lim TY, Laudier DM, Hecht AC, Weir MD, Weiser JR, Iatridis JC. Genipin-crosslinked fibrin seeded with oxidized alginate microbeads as a novel composite biomaterial strategy for intervertebral disc cell therapy. Biomaterials 2022; 287:121641. [PMID: 35759923 PMCID: PMC9758274 DOI: 10.1016/j.biomaterials.2022.121641] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/10/2022] [Accepted: 06/14/2022] [Indexed: 11/02/2022]
Abstract
Discectomy procedures alleviate disability caused by intervertebral disc (IVD) herniation, but do not repair herniation-induced annulus fibrosus (AF) defects. Cell therapy shows promise for IVD repair, yet cell delivery biomaterials capable of sealing AF defects and restoring biomechanical function have poor biological performance. To balance the biomechanical and biological demands of IVD cell delivery biomaterials, we engineered an injectable composite biomaterial using cell-laden, degradable oxidized alginate (OxAlg) microbeads (MBs) to deliver AF cells within high-modulus genipin-crosslinked fibrin (FibGen) hydrogels (FibGen + MB composites). Conceptually, the high-modulus FibGen would immediately stabilize injured IVDs, while OxAlg MBs would protect and release cells required for long-term healing. We first showed that AF cells microencapsulated in OxAlg MBs maintained high viability and, upon release, displayed phenotypic AF cell morphology and gene expression. Next, we created cell-laden FibGen + MB composites and demonstrated that OxAlg MBs functionalized with RGD peptides (MB-RGD) minimized AF cell apoptosis and retained phenotypic gene expression. Further, we showed that cell-laden FibGen + MB composites are biomechanically stable and promote extracellular matrix (ECM) synthesis in long-term in vitro culture. Lastly, we evaluated cell-laden FibGen + MB-RGD composites in a long-term bovine caudal IVD organ culture bioreactor and found that composites had low herniation risk, provided superior biomechanical and biological repair to discectomy controls, and retained anabolic cells within the IVD injury space. This novel injectable composite hydrogel strategy shows promise as an IVD cell delivery sealant with potentially broad applications for its capacity to balance biomechanical and biological performance.
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Affiliation(s)
- Christopher J Panebianco
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sanjna Rao
- Department of Chemical Engineering, The Cooper Union for the Advancement of Science and Art, New York, NY, USA
| | - Warren W Hom
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - James H Meyers
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Tiffany Y Lim
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Damien M Laudier
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Andrew C Hecht
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Michael D Weir
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD, USA
| | - Jennifer R Weiser
- Department of Chemical Engineering, The Cooper Union for the Advancement of Science and Art, New York, NY, USA
| | - James C Iatridis
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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21
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Tang SN, Walter BA, Heimann MK, Gantt CC, Khan SN, Kokiko-Cochran ON, Askwith CC, Purmessur D. In vivo Mouse Intervertebral Disc Degeneration Models and Their Utility as Translational Models of Clinical Discogenic Back Pain: A Comparative Review. FRONTIERS IN PAIN RESEARCH 2022; 3:894651. [PMID: 35812017 PMCID: PMC9261914 DOI: 10.3389/fpain.2022.894651] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/09/2022] [Indexed: 11/21/2022] Open
Abstract
Low back pain is a leading cause of disability worldwide and studies have demonstrated intervertebral disc (IVD) degeneration as a major risk factor. While many in vitro models have been developed and used to study IVD pathophysiology and therapeutic strategies, the etiology of IVD degeneration is a complex multifactorial process involving crosstalk of nearby tissues and systemic effects. Thus, the use of appropriate in vivo models is necessary to fully understand the associated molecular, structural, and functional changes and how they relate to pain. Mouse models have been widely adopted due to accessibility and ease of genetic manipulation compared to other animal models. Despite their small size, mice lumbar discs demonstrate significant similarities to the human IVD in terms of geometry, structure, and mechanical properties. While several different mouse models of IVD degeneration exist, greater standardization of the methods for inducing degeneration and the development of a consistent set of output measurements could allow mouse models to become a stronger tool for clinical translation. This article reviews current mouse models of IVD degeneration in the context of clinical translation and highlights a critical set of output measurements for studying disease pathology or screening regenerative therapies with an emphasis on pain phenotyping. First, we summarized and categorized these models into genetic, age-related, and mechanically induced. Then, the outcome parameters assessed in these models are compared including, molecular, cellular, functional/structural, and pain assessments for both evoked and spontaneous pain. These comparisons highlight a set of potential key parameters that can be used to validate the model and inform its utility to screen potential therapies for IVD degeneration and their translation to the human condition. As treatment of symptomatic pain is important, this review provides an emphasis on critical pain-like behavior assessments in mice and explores current behavioral assessments relevant to discogenic back pain. Overall, the specific research question was determined to be essential to identify the relevant model with histological staining, imaging, extracellular matrix composition, mechanics, and pain as critical parameters for assessing degeneration and regenerative strategies.
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Affiliation(s)
- Shirley N. Tang
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
| | - Benjamin A. Walter
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
- Department of Orthopaedics, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Mary K. Heimann
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
| | - Connor C. Gantt
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
| | - Safdar N. Khan
- Department of Orthopaedics, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Olga N. Kokiko-Cochran
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
- Institute for Behavioral Medicine Research, Neurological Institute, The Ohio State University, Columbus, OH, United States
| | - Candice C. Askwith
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
| | - Devina Purmessur
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
- Department of Orthopaedics, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
- *Correspondence: Devina Purmessur ;
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22
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Yang M, Xiang D, Wang S, Liu W. In Vitro Studies for Investigating Creep of Intervertebral Discs under Axial Compression: A Review of Testing Environment and Results. MATERIALS 2022; 15:ma15072500. [PMID: 35407833 PMCID: PMC9000064 DOI: 10.3390/ma15072500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/14/2022] [Accepted: 03/22/2022] [Indexed: 01/06/2023]
Abstract
Creep responses of intervertebral discs (IVDs) are essential for spinal biomechanics clarification. Yet, there still lacks a well-recognized investigation protocol for this phenomenon. Current work aims at providing researchers with an overview of the in vitro creep tests reported by previous studies, specifically specimen species, testing environment, loading regimes and major results, based on which a preliminary consensus that may guide future creep studies is proposed. Specimens used in creep studies can be simplified as a “bone–disc–bone” structure where three mathematical models can be adopted for describing IVDs’ responses. The preload of 10–50 N for 30 min or three cycles followed by 4 h-creep under constant compression is recommended for ex vivo simulation of physiological condition of long-time sitting or lying. It is worth noticing that species of specimens, environment temperature and humidity all have influences on biomechanical behaviors, and thus are summarized and compared through the literature review. All factors should be carefully set according to a guideline before tests are conducted to urge comparable results across studies. To this end, this review also provides a guideline, as mentioned before, and specific steps that might facilitate the community of biomechanics to obtain more repeatable and comparable results from both natural specimens and novel biomaterials.
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Affiliation(s)
- Mengying Yang
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China;
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China;
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China
| | - Dingding Xiang
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China;
- School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China
| | - Song Wang
- Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China
- Correspondence: (S.W.); (W.L.)
| | - Weiqiang Liu
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China;
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China
- Correspondence: (S.W.); (W.L.)
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Hickman TT, Rathan-Kumar S, Peck SH. Development, Pathogenesis, and Regeneration of the Intervertebral Disc: Current and Future Insights Spanning Traditional to Omics Methods. Front Cell Dev Biol 2022; 10:841831. [PMID: 35359439 PMCID: PMC8963184 DOI: 10.3389/fcell.2022.841831] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/09/2022] [Indexed: 02/06/2023] Open
Abstract
The intervertebral disc (IVD) is the fibrocartilaginous joint located between each vertebral body that confers flexibility and weight bearing capabilities to the spine. The IVD plays an important role in absorbing shock and stress applied to the spine, which helps to protect not only the vertebral bones, but also the brain and the rest of the central nervous system. Degeneration of the IVD is correlated with back pain, which can be debilitating and severely affects quality of life. Indeed, back pain results in substantial socioeconomic losses and healthcare costs globally each year, with about 85% of the world population experiencing back pain at some point in their lifetimes. Currently, therapeutic strategies for treating IVD degeneration are limited, and as such, there is great interest in advancing treatments for back pain. Ideally, treatments for back pain would restore native structure and thereby function to the degenerated IVD. However, the complex developmental origin and tissue composition of the IVD along with the avascular nature of the mature disc makes regeneration of the IVD a uniquely challenging task. Investigators across the field of IVD research have been working to elucidate the mechanisms behind the formation of this multifaceted structure, which may identify new therapeutic targets and inform development of novel regenerative strategies. This review summarizes current knowledge base on IVD development, degeneration, and regenerative strategies taken from traditional genetic approaches and omics studies and discusses the future landscape of investigations in IVD research and advancement of clinical therapies.
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Affiliation(s)
- Tara T. Hickman
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Sudiksha Rathan-Kumar
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Sun H. Peck
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- *Correspondence: Sun H. Peck,
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24
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Barcellona MN, Speer JE, Jing L, Patil DS, Gupta MC, Buchowski JM, Setton LA. Bioactive in situ crosslinkable polymer-peptide hydrogel for cell delivery to the intervertebral disc in a rat model. Acta Biomater 2021; 131:117-127. [PMID: 34229105 PMCID: PMC9157564 DOI: 10.1016/j.actbio.2021.06.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 12/11/2022]
Abstract
Degeneration of the intervertebral disc (IVD) is associated with
significant biochemical and morphological changes that include a loss of disc
height, decreased water content and decreased cellularity. Cell delivery has
been widely explored as a strategy to supplement the nucleus pulposus (NP)
region of the degenerated IVD in both pre-clinical and clinical trials, using
progenitor or primary cell sources. We previously demonstrated an ability for a
polymer-peptide hydrogel, serving as a culture substrate, to promote adult NP
cells to undergo a shift from a degenerative fibroblast-like state to a
juvenile-like NP phenotype. In the current study, we evaluate the ability for
this peptide-functionalized hydrogel to serve as a bioactive system for cell
delivery, retention and preservation of a biosynthetic phenotype for primary IVD
cells delivered to the rat caudal disc in an anular puncture degeneration model.
Our data suggest that encapsulation of adult degenerative human NP cells in a
stiff formulation of the hydrogel functionalized with laminin-mimetic peptides
IKVAV and AG73 can promote cell viability and increased biosynthetic activity
for this population in 3D culture in vitro. Delivery of the
peptide-functionalized biomaterial with primary rat cells to the degenerated IVD
supported NP cell retention and NP-specific protein expression in
vivo, and promoted improved disc height index (DHI) values and
endplate organization compared to untreated degenerated controls. The results of
this study suggest the physical cues of this peptide-functionalized hydrogel can
serve as a supportive carrier for cell delivery to the IVD.
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Affiliation(s)
- Marcos N Barcellona
- Department of Biomedical Engineering, Washington University in St. Louis, United States
| | - Julie E Speer
- Department of Biomedical Engineering, Washington University in St. Louis, United States
| | - Liufang Jing
- Department of Biomedical Engineering, Washington University in St. Louis, United States
| | - Deepanjali S Patil
- Department of Biomedical Engineering, Washington University in St. Louis, United States
| | - Munish C Gupta
- Department of Orthopedic Surgery, Washington University School of Medicine, United States
| | - Jacob M Buchowski
- Department of Orthopedic Surgery, Washington University School of Medicine, United States
| | - Lori A Setton
- Department of Biomedical Engineering, Washington University in St. Louis, United States; Department of Orthopedic Surgery, Washington University School of Medicine, United States.
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Oldweiler AB, Martin JT. In vivo relationships between lumbar facet joint and intervertebral disc composition and diurnal deformation. Clin Biomech (Bristol, Avon) 2021; 88:105425. [PMID: 34289433 PMCID: PMC8490326 DOI: 10.1016/j.clinbiomech.2021.105425] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/29/2021] [Accepted: 07/07/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Spinal motion is facilitated by a "three joint complex", two facet joints and one intervertebral disc at each spinal level. Both the intervertebral discs and facet joints are subject to natural age-related degeneration, and while these processes may be linked it is not clear how. As instability in the disc could underlie facet arthritis, we evaluated the hypothesis that the discs and facet joints are mechanically coupled. METHODS We recruited young, asymptomatic volunteers (n = 10; age: mean 25, range 21-30 years; BMI: mean 23.1, range 19.1-29.0 kg/m2) and applied magnetic resonance imaging (MRI) and three-dimensional (3D) modeling to measure facet and disc composition (MRI T1rho relaxation time) and facet and disc function (diurnal changes in facet space width, disc height) in the lumbar spine. FINDINGS We found that facet space width was positively associated with facet T1rho relaxation time (fluid content) and negatively associated with disc T1rho, and that facets adjacent to degenerated discs were significantly thicker and had significantly higher T1rho. Furthermore, the diurnal change in wedge angle was positively associated the diurnal change in facet space width, while disc degeneration, the diurnal change in disc height, and facet T1rho were not. INTERPRETATION These data demonstrate an interdependence between disc and facet health, but not between disc and facet mechanical function. Furthermore, the weak relationship between facet cartilage composition and in vivo function suggests that other factors, like spinal curvature, determine in vivo spine mechanics. Future work in symptomatic or aged populations are warranted to confirm these findings.
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Wang Y, Kang J, Guo X, Zhu D, Liu M, Yang L, Zhang G, Kang X. Intervertebral Disc Degeneration Models for Pathophysiology and Regenerative Therapy -Benefits and Limitations. J INVEST SURG 2021; 35:935-952. [PMID: 34309468 DOI: 10.1080/08941939.2021.1953640] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Aim:This review summarized the recent intervertebral disc degeneration (IDD) models and described their advantages and potential disadvantages, aiming to provide an overview for the current condition of IDD model establishment and new ideas for new strategies development of the treatment and prevention of IDD.Methods:The database of PubMed was searched up to May 2021 with the following search terms: nucleus pulposus, annulus fibrosus, cartilage endplate, intervertebral disc(IVD), intervertebral disc degeneration, animal model, organ culture, bioreactor, inflammatory reaction, mechanical stress, pathophysiology, epidemiology. Any IDD model-related articles were collected and summarized.Results:The best IDD model should have the features of repeatability, measurability and controllability. There are a lot of aspects to be considered in the selection of animals. Mice, rats and rabbits are low-cost and easy to access. However, their IVD size and shape are more different from human anatomy than pigs, cattle, sheep and goats. Organ culture models and animal models are two options in model establishment for IDD. The IVD organ culture model can put the studying variables into the controllable system for transitional research. Unlike the animal model, the organ culture model can only be used to evaluate the short-term effects and it is not applicable in simulating the complex process of IDD. Similarly, the animal models induced by different methods also have their advantages and disadvantages. For studying the mechanism of IDD and the corresponding treatment and prevention strategies, the selection of model should be individualized based on the purpose of each study.Conclusions:Various models have different characteristics and scope of application due to their different rationales and methods of construction. Currently, there is no experimental model that can perfectly mimic the degenerative process of human IVD. Personalized selection of appropriate model based on study purpose and experimental designing can enhance the possibility to obtain reliable and real results.
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Affiliation(s)
- Yidian Wang
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Jihe Kang
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Xudong Guo
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Daxue Zhu
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Mingqiang Liu
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Liang Yang
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Guangzhi Zhang
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China
| | - Xuewen Kang
- The Second Clinical Medical College, Lanzhou University, Lanzhou, P.R. China.,Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, P.R. China.,The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Gansu, P.R. China
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27
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Yokozeki Y, Uchida K, Kawakubo A, Nakawaki M, Okubo T, Miyagi M, Inoue G, Itakura M, Sekiguchi H, Takaso M. TGF-β regulates nerve growth factor expression in a mouse intervertebral disc injury model. BMC Musculoskelet Disord 2021; 22:634. [PMID: 34301215 PMCID: PMC8299674 DOI: 10.1186/s12891-021-04509-w] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 07/06/2021] [Indexed: 11/23/2022] Open
Abstract
Background Intervertebral disc (IVD) degeneration is a major cause of low back pain (LBP). Following disc injury, nerve growth factor (NGF) concentrations rise in IVDs, and anti-NGF therapy has been shown to attenuate LBP in humans. Increased levels of tumor necrosis factor-α (TNF-α) and transforming growth factor-β (TGF-β) in degenerative IVDs and in in vitro studies suggest that these factors promote NGF production. However, whether these factors regulate NGF in vivo remains unclear. Thus, we studied NGF regulation in a mouse model of IVD injury. Methods After inducing IVD injury, we examined mRNA levels of Tnfa, Tgfb, and Ngf in IVDs from control and IVD-injured mice across 7 days. To do this, we used magnetic cell separation to isolate CD11b ( +) (macrophage-rich) and CD11b (-) (IVD cell-rich) cell fractions from injured IVDs. To study the effect of TNF-α on Ngf expression, we examined Ngf expression in injured IVDs from C57BL/6 J and Tnfa-knockout (KO) mice (C57BL/6 J background). To study the effect of TGF-β on Ngf expression, C57/BL6J mice were given an intraperitoneal injection of either the TGF-β inhibitor SB431542 or DMSO solution (vehicle) one and two days before harvesting IVDs. Results mRNA expression of Tnfa, Tgfb, and Ngf was significantly increased in injured IVDs. Tnfa was predominantly expressed in the CD11b ( +) fraction, and Tgfb in the CD11b (-) fraction. Ngf expression was comparable between CD11b ( +) and CD11b (-) fractions, and between wild-type and Tnfa-KO mice at post-injury day (PID) 1, 3, and 7. SB431542 suppressed TGF-β-mediated Ngf expression and NGF production in vitro. Further, administration of SB431542 significantly reduced Ngf expression in IVDs such that levels were below those observed in vehicle-treated animals at PID3 and PID7. Conclusion A TGF-β inhibitor reduced Ngf expression in a mouse model of IVD injury, suggesting that TGF-β may regulate NGF expression in vivo. Supplementary Information The online version contains supplementary material available at 10.1186/s12891-021-04509-w.
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Affiliation(s)
- Yuji Yokozeki
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
| | - Kentaro Uchida
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan. .,Shonan University of Medical Sciences Research Institute, Nishikubo 500, Chigasaki City, Kanagawa, 253-0083, Japan.
| | - Ayumu Kawakubo
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
| | - Mitsufumi Nakawaki
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
| | - Tadashi Okubo
- Department of Laboratory Animal Science, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Masayuki Miyagi
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
| | - Gen Inoue
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
| | - Makoto Itakura
- Department of Biochemistry, Kitasato University School of Medicine, 1-15-1 Minami-ku, Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Hiroyuki Sekiguchi
- Shonan University of Medical Sciences Research Institute, Nishikubo 500, Chigasaki City, Kanagawa, 253-0083, Japan
| | - Masashi Takaso
- Department of Orthopaedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, Japan
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Zhang S, Song S, Zhuang Y, Hu J, Cui W, Wang X, Zhao Z, Liu X, Sun Z. RETRACTED: Role of microRNA-15a-5p/Sox9/NF-κB axis in inflammatory factors and apoptosis of murine nucleus pulposus cells in intervertebral disc degeneration. Life Sci 2021; 277:119408. [PMID: 33781831 DOI: 10.1016/j.lfs.2021.119408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 03/17/2021] [Accepted: 03/23/2021] [Indexed: 10/21/2022]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concerns were raised over the provenance of the flow cytometry plots in Figures 6G and 7F, as detailed here: https://pubpeer.com/publications/A46066C72A3E518DD6CA192362E0DC; and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. In addition, a portion of Figure 2G, ‘miR-15a-5p antagomir’ group appeared to contain image similarities with Figure 2G, ‘Oe-NC’ group. The journal requested that the corresponding author comment on these concerns and provide the raw data. The authors did not respond to this request and therefore the Editor-in-Chief decided to retract the article.
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Affiliation(s)
- Shujun Zhang
- Department of Spine Surgery, Wuxi 9th Affiliated Hospital of Soochow University, Wuxi 214000, Jiangsu, China; Department of Minimally Invasive Spine Surgery, Wuhan Pu'ai Hospital, Wuhan 430000, Hubei, China.
| | - Sheng Song
- Department of Spine Surgery, Wuxi 9th Affiliated Hospital of Soochow University, Wuxi 214000, Jiangsu, China
| | - Yin Zhuang
- Department of Spine Surgery, Wuxi 9th Affiliated Hospital of Soochow University, Wuxi 214000, Jiangsu, China
| | - Jun Hu
- Department of Minimally Invasive Spine Surgery, Wuhan Pu'ai Hospital, Wuhan 430000, Hubei, China
| | - Wei Cui
- Department of Minimally Invasive Spine Surgery, Wuhan Pu'ai Hospital, Wuhan 430000, Hubei, China
| | - Xin Wang
- Department of Minimally Invasive Spine Surgery, Wuhan Pu'ai Hospital, Wuhan 430000, Hubei, China
| | - Zhigang Zhao
- Department of Minimally Invasive Spine Surgery, Wuhan Pu'ai Hospital, Wuhan 430000, Hubei, China
| | - Xueguang Liu
- Department of Spine Surgery, Wuxi 9th Affiliated Hospital of Soochow University, Wuxi 214000, Jiangsu, China
| | - Zhenzhong Sun
- Department of Spine Surgery, Wuxi 9th Affiliated Hospital of Soochow University, Wuxi 214000, Jiangsu, China.
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Peng Y, Qing X, Shu H, Tian S, Yang W, Chen S, Lin H, Lv X, Zhao L, Chen X, Pu F, Huang D, Cao X, Shao Z, Yp, Zs, Xc, Yp, Yp, Xq, Hs, St, Wy, Yp, Xq, Hs, St, Hl, Xl, Lz, Xc, Fp, Sc, Yp, Xq, Hs, St, Yp, Xq, Wy, Hl, Xl, Lz, Xc, Fp, Sc, Hdh, Wy, Hl, Xl, Lz, Xc, Fp, Sc, Hdh, Zs, Xc. Proper animal experimental designs for preclinical research of biomaterials for intervertebral disc regeneration. BIOMATERIALS TRANSLATIONAL 2021; 2:91-142. [PMID: 35836965 PMCID: PMC9255780 DOI: 10.12336/biomatertransl.2021.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 06/09/2021] [Indexed: 01/17/2023]
Abstract
Low back pain is a vital musculoskeletal disease that impairs life quality, leads to disability and imposes heavy economic burden on the society, while it is greatly attributed to intervertebral disc degeneration (IDD). However, the existing treatments, such as medicines, chiropractic adjustments and surgery, cannot achieve ideal disc regeneration. Therefore, advanced bioactive therapies are implemented, including stem cells delivery, bioreagents administration, and implantation of biomaterials etc. Among these researches, few reported unsatisfying regenerative outcomes. However, these advanced therapies have barely achieved successful clinical translation. The main reason for the inconsistency between satisfying preclinical results and poor clinical translation may largely rely on the animal models that cannot actually simulate the human disc degeneration. The inappropriate animal model also leads to difficulties in comparing the efficacies among biomaterials in different reaches. Therefore, animal models that better simulate the clinical charateristics of human IDD should be acknowledged. In addition, in vivo regenerative outcomes should be carefully evaluated to obtain robust results. Nevertheless, many researches neglect certain critical characteristics, such as adhesive properties for biomaterials blocking annulus fibrosus defects and hyperalgesia that is closely related to the clinical manifestations, e.g., low back pain. Herein, in this review, we summarized the animal models established for IDD, and highlighted the proper models and parameters that may result in acknowledged IDD models. Then, we discussed the existing biomaterials for disc regeneration and the characteristics that should be considered for regenerating different parts of discs. Finally, well-established assays and parameters for in vivo disc regeneration are explored.
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Affiliation(s)
- Yizhong Peng
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xiangcheng Qing
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Hongyang Shu
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China,Hubei Key Laboratory of Genetics and Molecular Mechanism of Cardiologic Disorders, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Shuo Tian
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Wenbo Yang
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Songfeng Chen
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Hui Lin
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xiao Lv
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Lei Zhao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xi Chen
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Feifei Pu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Donghua Huang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Xu Cao
- Department of Orthopaedic Surgery, Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD, USA,Corresponding authors: Zengwu Shao, ; Xu Cao,
| | - Zengwu Shao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China,Corresponding authors: Zengwu Shao, ; Xu Cao,
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Promoting Nrf2/Sirt3-Dependent Mitophagy Suppresses Apoptosis in Nucleus Pulposus Cells and Protects against Intervertebral Disc Degeneration. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6694964. [PMID: 34211633 PMCID: PMC8211502 DOI: 10.1155/2021/6694964] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/11/2021] [Accepted: 04/29/2021] [Indexed: 12/22/2022]
Abstract
One of the causes of intervertebral disc degeneration (IVDD) is nucleus pulposus cell (NPC) death, possibly apoptosis. In this study, we explored the role of the Nrf2/Sirt3 pathway and tert-butylhydroquinone (t-BHQ) in IVDD and elucidated the potential working mechanism. Reactive oxygen species (ROS) assay kits and malondialdehyde (MDA) assay kits were used to assess oxidative stress. Western blot and TUNEL staining were used to examine apoptosis. After siRNA against Nrf2 or lentivirus against Sirt3 was transfected into NPCs, the mechanism of the effect of the Nrf2/Sirt3 pathway on NPCs was assessed. The interaction between t-BHQ and its potential interacting protein NRF2 was further investigated through protein docking analysis. ChIP examined the binding affinity between Nrf2 and Sirt3 promoter. In vivo experiments, X-ray, hematoxylin-eosin (HE) staining, Safranin O staining, and immunohistochemistry were used to evaluate IVDD grades. The results demonstrated that activation of the Nrf2/Sirt3 pathway inhibited tert-butyl hydroperoxide- (TBHP-) induced apoptosis and mitochondrial dysfunction in vitro. In addition to apoptosis, upregulation of the Nrf2/Sirt3 pathway induced by t-BHQ restored TBHP-induced autophagic flux disturbances. However, its protective effect was reversed by chloroquine and Si-ATG5. Furthermore, t-BHQ ameliorated IVDD development in a rat model. In conclusion, our findings indicate that the Nrf2/Sirt3 pathway and its agonist represent a potential candidate for treating IVDD.
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Wei Y, Tian Z, Tower RJ, Gullbrand S, Yao L, Shetye SS, Mauck RL, Qin L, Zhang Y. The Inner Annulus Fibrosus Encroaches on the Nucleus Pulposus in the Injured Mouse Tail Intervertebral Disc. Am J Phys Med Rehabil 2021; 100:450-457. [PMID: 32858534 PMCID: PMC8121249 DOI: 10.1097/phm.0000000000001575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The aim was to identify the source of cells within the center of the abnormal fibrocartilage tissue of the degenerative intervertebral disc after injury. DESIGN Cross-breeding of mice with an inducible type II promoter collagen construct (Col2CreER) to Rosa26-TdTomato mice has been shown to result in Cre-recombinase activity and Tomato expression in inner annulus fibrosus cells after tamoxifen injection. To investigate the role of the inner annulus fibrosus in the intervertebral disc injury response, tail intervertebral discs of Col2CreER/tdTomato mice were punctured with a needle and examined 1-4 wks after injury. N-cadherin was examined by immunostaining. RESULTS After the injury, the fibrocartilage in the degenerative intervertebral disc consisted of residual diseased nucleus pulposus cells and encroaching inner annulus fibrosus cells. The residual nucleus pulposus cells had lost their epithelial cell-like morphology and instead became oval shaped, with reduced adhesion to neighboring nucleus pulposus cells. This change in cellular morphology coincided with a loss of N-cadherin, which contributes to maintenance of healthy nucleus pulposus cell morphology. As expected, injured tail intervertebral discs showed reduced compressive properties as determined by biomechanical assessments. CONCLUSIONS The cellular composition of the degenerative intervertebral disc has been defined here, which is an important step in developing future treatments.
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Affiliation(s)
- Yulong Wei
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zuozhen Tian
- Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania
| | - Robert J. Tower
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
| | - Sarah Gullbrand
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
- Translational Musculoskeletal Research Center (TMRC), Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Lutian Yao
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
- Department of Orthopaedics/Sports Medicine and Joint Surgery, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, China
| | - Snehal S. Shetye
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
| | - Robert L. Mauck
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
- Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania
- Translational Musculoskeletal Research Center (TMRC), Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Ling Qin
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
| | - Yejia Zhang
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania
- Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania
- Translational Musculoskeletal Research Center (TMRC), Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
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Costi JJ, Ledet EH, O'Connell GD. Spine biomechanical testing methodologies: The controversy of consensus vs scientific evidence. JOR Spine 2021; 4:e1138. [PMID: 33778410 PMCID: PMC7984003 DOI: 10.1002/jsp2.1138] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022] Open
Abstract
Biomechanical testing methodologies for the spine have developed over the past 50 years. During that time, there have been several paradigm shifts with respect to techniques. These techniques evolved by incorporating state-of-the-art engineering principles, in vivo measurements, anatomical structure-function relationships, and the scientific method. Multiple parametric studies have focused on the effects that the experimental technique has on outcomes. As a result, testing methodologies have evolved, but there are no standard testing protocols, which makes the comparison of findings between experiments difficult and conclusions about in vivo performance challenging. In 2019, the international spine research community was surveyed to determine the consensus on spine biomechanical testing and if the consensus opinion was consistent with the scientific evidence. More than 80 responses to the survey were received. The findings of this survey confirmed that while some methods have been commonly adopted, not all are consistent with the scientific evidence. This review summarizes the scientific literature, the current consensus, and the authors' recommendations on best practices based on the compendium of available evidence.
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Affiliation(s)
- John J. Costi
- Biomechanics and Implants Research Group, Medical Device Research Institute, College of Science and EngineeringFlinders UniversityAdelaideAustralia
| | - Eric H. Ledet
- Department of Biomedical EngineeringRensselaer Polytechnic InstituteTroyNew YorkUSA
- Research and Development ServiceStratton VA Medical CenterAlbanyNew YorkUSA
| | - Grace D. O'Connell
- Department of Mechanical EngineeringUniversity of California‐BerkeleyBerkeleyCaliforniaUSA
- Department of Orthopaedic SurgeryUniversity of California‐San FranciscoSan FranciscoCaliforniaUSA
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Li Y, Liu S, Pan D, Xu B, Xing X, Zhou H, Zhang B, Zhou S, Ning G, Feng S. The potential role and trend of HIF‑1α in intervertebral disc degeneration: Friend or foe? (Review). Mol Med Rep 2021; 23:239. [PMID: 33537810 PMCID: PMC7893690 DOI: 10.3892/mmr.2021.11878] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 11/08/2019] [Indexed: 12/11/2022] Open
Abstract
Lower back pain (LBP) is one of the most common reasons for seeking medical advice in orthopedic clinics. Increasingly, research has shown that symptomatic intervertebral disc degeneration (IDD) is mostly related to LBP. This review first outlines the research and findings of studies into IDD, from the physiological structure of the intervertebral disc (IVD) to various pathological cascades. The vicious cycles of IDD are re-described in relation to the analysis of the relationship among the pathological mechanisms involved in IDD. Interestingly, a ‘chief molecule’ was found, hypoxia-inducible factor-1α (HIF-1α), that may regulate all other mechanisms involved in IDD. When the vicious cycle is established, the low oxygen tension activates the expression of HIF-1α, which subsequently enters into the hypoxia-induced HIF pathways. The HIF pathways are dichotomized as friend and foe pathways according to the oxygen tension of the IVD microenvironment. Combined with clinical outcomes and previous research, the trend of IDD development has been predicted in this paper. Lastly, an early precautionary diagnosis and treatment method is proposed whereby nucleus pulposus tissue for biopsy can be obtained through IVD puncture guided by B-ultrasound when the patient is showing symptoms but MRI imaging shows negative results. The assessment criteria for biopsy and the feasibility, superiority and challenges of this approach have been discussed. Overall, it is clear that HIF-1α is an indispensable reference indicator for the accurate diagnosis and treatment of IDD.
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Affiliation(s)
- Yongjin Li
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Shen Liu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Dayu Pan
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Baoshan Xu
- Department of Spine Surgery, Tianjin Hospital, Tianjin 300000, P.R. China
| | - Xuewu Xing
- Department of Orthopedic Surgery, First Central Clinical of Tianjin Medical University, Tianjin 300052, P.R. China
| | - Hengxing Zhou
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Bin Zhang
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Suzhe Zhou
- Department of Orthopedics, The Affiliated Zhongshan Hospital of Fudan University, Shanghai 200034, P.R. China
| | - Guangzhi Ning
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Shiqing Feng
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
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Serjeant M, Moon PM, Quinonez D, Penuela S, Beier F, Séguin CA. The Role of Panx3 in Age-Associated and Injury-Induced Intervertebral Disc Degeneration. Int J Mol Sci 2021; 22:ijms22031080. [PMID: 33499145 PMCID: PMC7865929 DOI: 10.3390/ijms22031080] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/06/2021] [Accepted: 01/19/2021] [Indexed: 01/08/2023] Open
Abstract
Pannexin 3 (Panx3) is a mechanosensitive, channel-forming glycoprotein implicated in the progression of post-traumatic osteoarthritis. Despite evidence for Panx3 expression in the intervertebral disc (IVD), its function in this cartilaginous joint structure remained unknown. Using Panx3 knockout mice, this study investigated the role of Panx3 in age-associated IVD degeneration and degeneration induced by annulus fibrosus (AF) needle puncture. Loss of Panx3 did not significantly impact the progression of age-associated histopathological IVD degeneration; however, loss of Panx3 was associated with decreased gene expression of Acan, Col1a1, Mmp13 and Runx2 and altered localization of COLX in the IVD at 19 months-of-age. Following IVD injury in the caudal spine, histological analysis of wild-type mice revealed clusters of hypertrophic cells in the AF associated with increased pericellular proteoglycan accumulation, disruptions in lamellar organization and increased lamellar thickness. In Panx3 knockout mice, hypertrophic AF cells were rarely detected and AF structure was largely preserved post-injury. Interestingly, uninjured IVDs adjacent to the site of injury more frequently showed evidence of early nucleus pulposus degeneration in Panx3 knockout mice but remained healthy in wild-type mice. These findings suggest a role for Panx3 in mediating the adaptive cellular responses to altered mechanical stress in the IVD, which may buffer aberrant loads transferred to adjacent motion segments.
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Affiliation(s)
- Meaghan Serjeant
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (P.M.M.); (D.Q.); (F.B.)
- Bone and Joint Institute, The University of Western Ontario, London, ON N6A 5C1, Canada;
| | - Paxton M. Moon
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (P.M.M.); (D.Q.); (F.B.)
- Bone and Joint Institute, The University of Western Ontario, London, ON N6A 5C1, Canada;
| | - Diana Quinonez
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (P.M.M.); (D.Q.); (F.B.)
| | - Silvia Penuela
- Bone and Joint Institute, The University of Western Ontario, London, ON N6A 5C1, Canada;
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Frank Beier
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (P.M.M.); (D.Q.); (F.B.)
- Bone and Joint Institute, The University of Western Ontario, London, ON N6A 5C1, Canada;
| | - Cheryle A. Séguin
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (P.M.M.); (D.Q.); (F.B.)
- Bone and Joint Institute, The University of Western Ontario, London, ON N6A 5C1, Canada;
- Correspondence:
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Zhang Y, Tian Z, Gerard D, Yao L, Shofer FS, Cs-Szabo G, Qin L, Pacifici M, Enomoto-Iwamoto M. Elevated inflammatory gene expression in intervertebral disc tissues in mice with ADAM8 inactivated. Sci Rep 2021; 11:1804. [PMID: 33469101 PMCID: PMC7815795 DOI: 10.1038/s41598-021-81495-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 12/31/2020] [Indexed: 12/24/2022] Open
Abstract
We found ADAM8 enzymatic activity elevated in degenerative human intervertebral disc (IVD). Here, we examined the discs in ADAM8-inactivation mice that carry a mutation preventing self-activation of the enzyme. Surprisingly, elevated gene expression for inflammatory markers (Cxcl1, IL6) was observed in injured discs of ADAM8 mutant mice, along with elevated expression of type 2 collagen gene (Col2a1), compared with wild type controls. Injured annulus fibrosus of mutant and wild type mice contained a higher proportion of large collagen fibers compared with intact discs, as documented by microscopic examination under circular polarized light. In the intact IVDs, Adam8EQ mouse AF contained lower proportion of yellow (intermediate) fiber than WT mice. This suggests that ADAM8 may regulate inflammation and collagen fiber assembly. The seemingly contradictory findings of elevated inflammatory markers in mutant mice and excessive ADAM8 activity in human degenerative discs suggest that ADAM8 may interact with other enzymatic and pro-inflammatory processes needed for tissue maintenance and repair. As a future therapeutic intervention to retard intervertebral disc degeneration, partial inhibition of ADAM8 proteolysis may be more desirable than complete inactivation of this enzyme.
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Affiliation(s)
- Yejia Zhang
- Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA.
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA.
- Translational Musculoskeletal Research Center (TMRC), Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA.
| | - Zuozhen Tian
- Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - David Gerard
- Department of Biochemistry, Rush University Medical Center, Chicago, IL, USA
| | - Lutian Yao
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
- Department of Orthopaedics/Sports Medicine and Joint Surgery, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, China
| | - Frances S Shofer
- Emergency Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Gabriella Cs-Szabo
- Department of Biochemistry, Rush University Medical Center, Chicago, IL, USA
| | - Ling Qin
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Maurizio Pacifici
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, USA
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Hoy RC, D'Erminio DN, Krishnamoorthy D, Natelson DM, Laudier DM, Illien‐Jünger S, Iatridis JC. Advanced glycation end products cause RAGE-dependent annulus fibrosus collagen disruption and loss identified using in situ second harmonic generation imaging in mice intervertebral disk in vivo and in organ culture models. JOR Spine 2020; 3:e1126. [PMID: 33392460 PMCID: PMC7770195 DOI: 10.1002/jsp2.1126] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 08/12/2020] [Accepted: 09/09/2020] [Indexed: 12/13/2022] Open
Abstract
Aging and diabetes are associated with increased low-back pain and intervertebral disk (IVD) degeneration yet causal mechanisms remain uncertain. Advanced glycation end products (AGEs), which accumulate in IVDs from aging and are implicated in diabetes-related disorders, alter collagen and induce proinflammatory conditions. A need exists for methods that assess IVD collagen quality and degradation in order to better characterize specific structural changes in IVDs due to AGE accumulation and to identify roles for the receptor for AGEs (RAGE). We used multiphoton microscopy with second harmonic generation (SHG), collagen-hybridizing peptide (CHP), and image analysis methods to characterize effects of AGEs and RAGE on collagen quality and quantity in IVD annulus fibrosus (AF). First, we used SHG imaging on thin sections with an in vivo dietary mouse model and determined that high-AGE (H-AGE) diets increased AF fibril disruption and collagen degradation resulting in decreased total collagen content, suggesting an early degenerative cascade. Next, we used in situ SHG imaging with an ex vivo IVD organ culture model of AGE challenge on wild type and RAGE-knockout (RAGE-KO) mice and determined that early degenerative changes to collagen quality and degradation were RAGE dependent. We conclude that AGE accumulation leads to RAGE-dependent collagen disruption in the AF and can initiate molecular and tissue level collagen disruption. Furthermore, SHG and CHP analyzes were sensitive to collagenous alterations at multiple hierarchical levels due to AGE and may be useful in identifying additional contributors to collagen damage in IVD degeneration processes.
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Affiliation(s)
- Robert C. Hoy
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
| | - Danielle N. D'Erminio
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
| | - Divya Krishnamoorthy
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
| | - Devorah M. Natelson
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
| | - Damien M. Laudier
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
| | | | - James C. Iatridis
- Leni & Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNYUnited StatesUSA
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Zhang X, Huang Z, Xie Z, Chen Y, Zheng Z, Wei X, Huang B, Shan Z, Liu J, Fan S, Chen J, Zhao F. Homocysteine induces oxidative stress and ferroptosis of nucleus pulposus via enhancing methylation of GPX4. Free Radic Biol Med 2020; 160:552-565. [PMID: 32896601 DOI: 10.1016/j.freeradbiomed.2020.08.029] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/19/2020] [Accepted: 08/30/2020] [Indexed: 12/16/2022]
Abstract
Homocysteine (Hcy) is an amino acid involved in gene methylation. Plasma concentration of Hcy is elevated in the pathological condition hyperhomocysteinemia (HHcy), which increases the risk of disorders of the vascular, nervous and musculoskeletal systems, including chondrocyte dysfunction. The present study aimed to explore the role of Hcy in intervertebral disc degeneration (IVDD), using a range of techniques. A clinical epidemiological study showed that HHcy is an independent risk factor for human IVDD. Cell culture using rat nucleus pulposus cells showed that Hcy promotes a degenerative cell phenotype (involving increased oxidative stress and cell death by ferroptosis) which is mediated by upregulated methylation of GPX4. An in-vivo mouse 'puncture' model of IVDD showed that folic acid (which is used to treat HHcy in humans) reduced the ability of diet-induced HHcy to promote IVDD. We conclude that Hcy upregulates oxidative stress and ferroptosis in the nucleus pulposus via enhancing GPX4 methylation, and is a new contributing factor in IVDD.
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Affiliation(s)
- Xuyang Zhang
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Zhaobo Huang
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Ziang Xie
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Yilei Chen
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Zeyu Zheng
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Xiao'an Wei
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Bao Huang
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Zhi Shan
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Junhui Liu
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Shunwu Fan
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Jian Chen
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
| | - Fengdong Zhao
- Department of Orthopaedics, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3, Qingchun Road East, Hangzhou, 310016, PR China; Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province, PR China.
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Ashinsky BG, Gullbrand SE, Wang C, Bonnevie ED, Han L, Mauck RL, Smith HE. Degeneration alters structure-function relationships at multiple length-scales and across interfaces in human intervertebral discs. J Anat 2020; 238:986-998. [PMID: 33205444 DOI: 10.1111/joa.13349] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 09/19/2020] [Accepted: 10/08/2020] [Indexed: 12/19/2022] Open
Abstract
Intervertebral disc (IVD) degeneration and associated back pain place a significant burden on the population. IVD degeneration is a progressive cascade of cellular, compositional, and structural changes, which results in a loss of disc height, disorganization of extracellular matrix architecture, tears in the annulus fibrosus which may involve herniation of the nucleus pulposus, and remodeling of the bony and cartilaginous endplates (CEP). These changes to the IVD often occur concomitantly, across the entire motion segment from the disc subcomponents to the CEP and vertebral bone, making it difficult to determine the causal initiating factor of degeneration. Furthermore, assessments of the subcomponents of the IVD have been largely qualitative, with most studies focusing on a single attribute, rather than multiple adjacent IVD substructures. The objective of this study was to perform a multiscale and multimodal analysis of human lumbar motion segments across various length scales and degrees of degeneration. We performed multiple assays on every sample and identified several correlations between structural and functional measurements of disc subcomponents. Our results demonstrate that with increasing Pfirrmann grade there is a reduction in disc height and nucleus pulposus T2 relaxation time, in addition to alterations in motion segment macromechanical function, disc matrix composition and cellular morphology. At the cartilage endplate-vertebral bone interface, substantial remodeling was observed coinciding with alterations in micromechanical properties. Finally, we report significant relationships between vertebral bone and nucleus pulposus metrics, as well as between micromechanical properties of the endplate and whole motion segment biomechanical parameters, indicating the importance of studying IVD degeneration as a whole organ.
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Affiliation(s)
- Beth G Ashinsky
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Drexel University School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA.,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Sarah E Gullbrand
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Chao Wang
- Drexel University School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA
| | - Edward D Bonnevie
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Lin Han
- Drexel University School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA
| | - Robert L Mauck
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Harvey E Smith
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
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Cauble MA, Mancini NS, Kalinowski J, Lykotrafitis G, Moss IL. Atomic force microscopy imaging for nanoscale and microscale assessments of extracellular matrix in intervertebral disc and degeneration. JOR Spine 2020; 3:e1125. [PMID: 33015582 PMCID: PMC7524250 DOI: 10.1002/jsp2.1125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/07/2020] [Accepted: 08/30/2020] [Indexed: 01/07/2023] Open
Abstract
Degeneration of the intervertebral disc (IVD) is a condition that is often associated with debilitating back pain. There are no disease-modifying treatments available to halt the progression of this ubiquitous disorder. This is partly due to a lack of understanding of extracellular matrix (ECM) changes that occur at the micro- and nanometer size scales as the disease progresses. Over the past decade, atomic force microscopy (AFM) has been utilized as a tool to investigate the impact of disease on nanoscale structure of ECM in bone, skin, tendon, and dentin. We have expanded this methodology to include the IVD and report the first quantitative analysis of ECM structure at submicron size scales in a murine model for progressive IVD degeneration. Collagen D-spacing, a metric of nanoscale structure at the fibril level, was observed as a distribution of values with an overall average value of 62.5 ± 2.5 nm. In degenerative discs, the fibril D-spacing distribution shifted towards higher values in both the annulus fibrosus and nucleus pulposus (NP) (P < .05). A novel microstructural feature, collagen toroids, defined by a topographical pit enclosed by fibril-forming matrix was observed in the NP. With degeneration, these microstructures became more numerous and the morphology was altered from circular (aspect ratio 1.0 ± 0.1) to oval (aspect ratio 1.5 ± 0.4), P < .005. These analyses provide ECM structural details of the IVD at size scales that have historically been missing in studies of disc degeneration. Knowledge gained from these insights may aid the development of novel disease-modifying therapeutics.
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Affiliation(s)
- Meagan A Cauble
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - Nickolas S Mancini
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - Judith Kalinowski
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - George Lykotrafitis
- Department of Mechanical Engineering University of Connecticut Storrs Connecticut USA
| | - Isaac L Moss
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
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40
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Su QH, Zhang Y, Shen B, Li YC, Tan J. Application of molybdenum target X-ray photography in imaging analysis of caudal intervertebral disc degeneration in rats. World J Clin Cases 2020; 8:3431-3439. [PMID: 32913849 PMCID: PMC7457105 DOI: 10.12998/wjcc.v8.i16.3431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/09/2020] [Accepted: 07/16/2020] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Conventional plain X-ray images of rats, the most common animals used as degeneration models, exhibit unclear vertebral structure and blurry intervertebral disc spaces due to their small size, slender vertebral bodies.
AIM To apply molybdenum target X-ray photography in the evaluation of caudal intervertebral disc (IVD) degeneration in rat models.
METHODS Two types of rat caudal IVD degeneration models (needle-punctured model and endplate-destructed model) were established, and their effectiveness was verified using nuclear magnetic resonance imaging. Molybdenum target inspection and routine plain X-ray were then performed on these models. Additionally, four observers were assigned to measure the intervertebral height of degenerated segments on molybdenum target plain X-ray images and routine plain X-ray images, respectively. The degeneration was evaluated and statistical analysis was subsequently conducted.
RESULTS Nine rats in the needle-punctured model and 10 rats in the endplate-destructed model were effective. Compared with routine plain X-ray images, molybdenum target plain X-ray images showed higher clarity, stronger contrast, as well as clearer and more accurate structural development. The McNemar test confirmed that the difference was statistically significant (P = 0.031). In the two models, the reliability of the intervertebral height measured by the four observers on routine plain X-ray images was poor (ICC < 0.4), while the data obtained from the molybdenum target plain X-ray images were more reliable.
CONCLUSION Molybdenum target inspection can obtain clearer images and display fine calcification in the imaging evaluation of caudal IVD degeneration in rats, thus ensuring a more accurate evaluation of degeneration.
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Affiliation(s)
- Qi-Hang Su
- Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Yan Zhang
- Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Bin Shen
- Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Yong-Chao Li
- Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Jun Tan
- Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
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Ashinsky BG, Gullbrand SE, Bonnevie ED, Wang C, Kim DH, Han L, Mauck RL, Smith HE. Sacrificial Fibers Improve Matrix Distribution and Micromechanical Properties in a Tissue-Engineered Intervertebral Disc. Acta Biomater 2020; 111:232-241. [PMID: 32447064 DOI: 10.1016/j.actbio.2020.05.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/19/2022]
Abstract
Tissue-engineered replacement discs are an area of intense investigation for the treatment of end-stage intervertebral disc (IVD) degeneration. These living implants can integrate into the IVD space and recapitulate native motion segment function. We recently developed a multiphasic tissue-engineered disc-like angle-ply structure (DAPS) that models the micro-architectural and functional features of native tissue. While these implants resulted in functional restoration of the motion segment in rat and caprine models, we also noted deficiencies in cell infiltration and homogeneity of matrix deposition in the electrospun poly(ε-caprolactone) outer region (annulus fibrosus, AF) of the DAPS. To address this limitation, here, we incorporated a sacrificial water-soluble polymer, polyethylene oxide (PEO), as a second fiber fraction within the AF region to increase porosity of the implant. Maturation of these PEO-modified DAPS were evaluated after 5 and 10 weeks of in vitro culture in terms of AF biochemical content, MRI T2 values, overall construct mechanical properties, AF micromechanical properties and cell and matrix distribution. To assess the performance of the PEO-modified DAPS in vivo, precultured constructs were implanted into the rat caudal IVD space for 10 weeks. Results showed that matrix distribution was more homogenous in PCL/PEO DAPS, as evidenced by more robust histological staining, organized collagen deposition and micromechanical properties, compared to standard PCL-only DAPS in vitro. Cell and matrix infiltration were also improved in vivo, but no differences in macromechanical properties and a trend towards improved micromechanical properties were observed. These findings demonstrate that the inclusion of a sacrificial PEO fiber fraction in the DAPS AF region improves cellular colonization, matrix elaboration, and in vitro and in vivo function of an engineered IVD implant. STATEMENT OF SIGNIFICANCE: This work establishes a method for improving cell infiltration and matrix distribution within tissue-engineered dense fibrous scaffolds for intervertebral disc replacement. Tissue-engineered whole disc replacements are an attractive alternative to the current gold standard (mechanical disc arthroplasty or vertebral fusion) for the clinical treatment of patients with advanced disc degeneration.
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Tian Z, Shofer FS, Yao L, Sun H, Zhang H, Qin L, Chen YH, Zhang Y. TNFAIP8 family gene expressions in the mouse tail intervertebral disc injury model. JOR Spine 2020; 3:e1093. [PMID: 32613168 PMCID: PMC7323467 DOI: 10.1002/jsp2.1093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/25/2020] [Accepted: 05/08/2020] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION The TNF-α-induced protein-8 (TNFAIP8, also known as TIPE) family of molecules comprises four members: TNFAIP8 and TIPEs1-3. Since the first description of these proteins, their roles in fine-tuning inflammation and in directing leukocyte migration have been described in several organ systems. However, their relationship with intervertebral disc (IVD) is unknown. MATERIALS AND METHODS Here, we describe the expression of TNFAIP8 family genes in the nucleus pulposus (NP) and annulus fibrosus (AF) of the normal adult murine IVD. We further describe the expression of these genes in the injured male and female murine IVD. RESULTS Tnfaip8 gene expression was decreased, and Tipe1 gene expression was essentially unchanged, in response to injury. Tipe2 and Tipe3 gene expression was markedly elevated in response to IVD injury, along with those encoding known inflammatory markers (ie, Tnfa, Il6, Cxcl1, and Adam8). Additionally, sex-related differences were also observed for some of these genes in intact and injured mouse IVDs. Future studies include examining tissue distribution of TNFAIP8 family proteins and identifying cells that produce them. In addition, examining mice that are deficient in TNFAIP8 molecules, in relation to gene expression, tissue morphology and mouse behavior, may further delineate the roles of these molecules in IVD inflammation and degeneration.
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Affiliation(s)
- Zuozhen Tian
- Department of Physical Medicine & RehabilitationUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Frances S. Shofer
- Department of Emergency MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Lutian Yao
- Department of Orthopaedic SurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of Orthopaedics/Sports Medicine and Joint Surgery, First Affiliated HospitalChina Medical UniversityShenyangLiaoningChina
| | - Honghong Sun
- Pathology and Laboratory Medicine, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Hongtao Zhang
- Pathology and Laboratory Medicine, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Ling Qin
- Department of Emergency MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Youhai H. Chen
- Pathology and Laboratory Medicine, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Yejia Zhang
- Department of Physical Medicine & RehabilitationUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of Orthopaedic SurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research Center (TMRC)Corporal Michael J. Crescenz Veterans Affairs Medical CenterPhiladelphiaPennsylvaniaUSA
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Lee S, Millecamps M, Foster DZ, Stone LS. Long-term histological analysis of innervation and macrophage infiltration in a mouse model of intervertebral disc injury-induced low back pain. J Orthop Res 2020; 38:1238-1247. [PMID: 31814143 DOI: 10.1002/jor.24560] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 12/04/2019] [Indexed: 02/04/2023]
Abstract
Low back pain (LBP) is a leading cause of global disability. Multiple anatomical, cellular, and molecular factors are implicated in LBP, including the degeneration of lumbar intervertebral discs (IVDs). We previously described a mouse model that displays behavioral symptoms of chronic LBP. Here, we investigated the development of pathological innervation and macrophage infiltration into injured IVDs following a puncture injury in mice over 12 months. 2-month old CD1 female mice underwent a single puncture of the ventral L4/5 IVD using a 30G needle, and were sacrificed 4 days and 0.5-, 3-, 6- and 12-months post-injury. Severity of disc degeneration was assessed using colorimetric staining. IVD innervation was measured by PGP9.5-immunoreactivity (-ir) and calcitonin gene-related peptide-ir (CGRP-ir). Macrophage accumulation into IVDs was detected by F4/80-ir. Mechanical IVD injury resulted in severe degeneration and increased PGP9.5-ir nerve fiber density starting at 4 days that persisted for up to 12 months and dorsal herniations began to occur at 3 months. CGRP-ir was also upregulated in injured IVDs, with the largest increase at 12 months after injury. Infiltration of F4/80-ir macrophages was observed in injured IVDs by day 4 both dorsally and ventrally, with the latter diminishing in the later stage. Persistent LBP is a complex disease with multiple underlying pathologies. By highlighting pathological changes in IVD innervation and inflammation, our study suggests that strategies targeting these mechanisms might be useful therapeutically.
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Affiliation(s)
- Seunghwan Lee
- Faculty of Dentistry, McGill University, Montreal, Quebec, Canada.,The Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Magali Millecamps
- Faculty of Dentistry, McGill University, Montreal, Quebec, Canada.,The Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Daniel Z Foster
- Faculty of Dentistry, McGill University, Montreal, Quebec, Canada.,The Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Laura S Stone
- Faculty of Dentistry, McGill University, Montreal, Quebec, Canada.,The Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada.,Departments of Anesthesiology, Pharmacology & Therapeutics, Neurology and Neurosurgery, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
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Nonlinear stress-dependent recovery behavior of the intervertebral disc. J Mech Behav Biomed Mater 2020; 110:103881. [PMID: 32957189 DOI: 10.1016/j.jmbbm.2020.103881] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/22/2020] [Accepted: 05/23/2020] [Indexed: 12/17/2022]
Abstract
The intervertebral disc exhibits complex mechanics due to its heterogeneous structure, inherent viscoelasticity, and interstitial fluid-matrix interactions. Sufficient fluid flow into the disc during low loading periods is important for maintaining mechanics and nutrient transport. However, there is a lack of knowledge on the effect of loading magnitude on time-dependent recovery behavior and the relative contribution of multiple recovery mechanisms during recovery. In most studies that have evaluated disc recovery behavior, a single load condition has been considered, making it difficult to compare findings across studies. Hence, the objective of this study was to quantify unloaded disc recovery behavior after compressive creep loading under a wide range of physiologically relevant stresses (0.2-2 MPa). First, the repeatability of disc recovery behavior was assessed. Once repeatable recovery behavior was confirmed, each motion segment was subject to three cycles of creep-recovery loading, where each cycle consisted of a 24-h creep at a pre-assigned load (100, 200, 300, 600, 900, or 1200 N), followed by an 18-h recovery period at a nominal load (10 N). Results showed that disc recovery behavior was strongly influenced by the magnitude of loading. The magnitude of instantaneous and time-dependent recovery deformations increased nonlinearly with an increase in compressive stress during creep. In conclusion, this study highlights that elastic deformation, intrinsic viscoelasticity, and poroelasticity all have substantial contributions to disc height recovery during low loading periods. However, their relative contributions to disc height recovery largely depend on the magnitude of loading. While loading history does not influence the contribution of the short-term recovery, the contribution of long-term recovery is highly sensitive to loading magnitude.
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Brent JM, Tian Z, Shofer FS, Martin JT, Yao L, Acharte C, Chen YH, Qin L, Enomoto-Iwamoto M, Zhang Y. Influence of Genetic Background and Sex on Gene Expression in the Mouse ( Mus musculus) Tail in a Model of Intervertebral Disc Injury. Comp Med 2020; 70:131-139. [PMID: 32156324 PMCID: PMC7137552 DOI: 10.30802/aalas-cm-19-000034] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/08/2019] [Accepted: 07/26/2019] [Indexed: 11/05/2022]
Abstract
To facilitate rational experimental design and fulfill the NIH requirement of including sex as a biologic variable, we examined the influences of genetic background and sex on responses to intervertebral disc (IVD) injury in the mouse tail. The goal of this study was to compare gene expression and histologic changes in response to a tail IVD injury (needle puncture) in male and female mice on the DBA and C57BL/6 (B6) backgrounds. We hypothesized that extracellular matrix gene expression in response to IVD injury differs between mice of different genetic backgrounds and sex. Consistent changes were detected in gene expression and histologic features after IVD injury in mice on both genetic backgrounds and sexes. In particular, expression of col1a1 and adam8 was higher in the injured IVD of DBA mice than B6 mice. Conversely, col2a1 expression was higher in B6 mice than DBA mice. Sex-associated differences were significant only in B6 mice, in which col2a1 expression was greater in male mice than in female. Histologic differences in response to injury were not apparent between DBA and B6 mice or between males and females. In conclusion, mouse tail IVD showed sex- and strain-related changes in gene expression and histology after needle puncture. The magnitude of change in gene expression differed with regard to genetic background and, to a lesser degree, sex.
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Affiliation(s)
- Julie M Brent
- University Laboratory Animal Resources, University of Pennsylvania, Philadelphia, Pennsylvania;,
| | - Zuozhen Tian
- Departments of Physical Medicine and Rehabilitation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Frances S Shofer
- Departments of Emergency Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - John T Martin
- Departments of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Translational Musculoskeletal Research Center, Corporal Michael J Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania
| | - Lutian Yao
- Departments of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Orthopaedics-Sports Medicine and Joint Surgery, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, China
| | - Christian Acharte
- Departments of Physical Medicine and Rehabilitation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Youhai H Chen
- Departments of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ling Qin
- Departments of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Motomi Enomoto-Iwamoto
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Yejia Zhang
- Departments of Physical Medicine and Rehabilitation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Departments of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Translational Musculoskeletal Research Center, Corporal Michael J Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania
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Hsu HT, Yue CT, Teng MS, Tzeng IS, Li TC, Tai PA, Huang KF, Chen CY, Ko YL. Immuohistochemical score of matrix metalloproteinase-1 may indicate the severity of symptomatic cervical and lumbar disc degeneration. Spine J 2020; 20:124-137. [PMID: 31408735 DOI: 10.1016/j.spinee.2019.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/24/2019] [Accepted: 08/07/2019] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Intervertebral disc (IVD) degeneration is related to numerous risk factors, including obesity. Leptin, one of the commonly measured adipokines, is proven to play an important role in the pathogenesis of IVD degeneration. In the context of IVD degeneration, matrix metalloproteinase-1 (MMP-1), which is upregulated and activated by leptin, is the most abundant catabolic enzyme. It remains unclear which of the factors mentioned above is most strongly associated with IVD degeneration. PURPOSE To investigate the influence of MMP-1 in IVD degeneration, we determined the strength of different predictors, including age, sex, magnetic resonance imaging (MRI), Modic changes (MCs), body mass index (BMI), leptin, and MMP-1. This was achieved by assessing the correlation among these factors and histologic degeneration score (HDS). STUDY DESIGN This study included 89 patients undergoing cervical discectomy for disc herniation, 93 who underwent lumbar discectomy, and 90 control subjects. Herniated disc tissue and plasma were used after the study was approved by the Human Ethics Review Committee at the authors' institution. METHODS Hematoxylin and eosin (H&E), Alcian blue-PAS and immunohistochemical (IHC) staining were performed to measure the expression levels of leptin and MMP-1. Circulating plasma levels of leptin and MMP-1 were measured using an enzyme-linked immunosorbent assay. To assess the correlation with HDS, measurements of age, sex, BMI, MRI scale, MCs scale, leptin/MMP-1 plasma concentration, and leptin/MMP-1 IHC expression were analyzed. RESULTS Patients with cervical or lumbar discectomy had significantly higher BMI than controls. Significantly more men than women were involved in the lumbar patients as compared with the cervical patients and the control subjects. After adjustment for age and sex, plasma leptin and leptin IHC score correlated significantly with BMI in patients with cervical or lumbar discectomy. Age, sex, MRI scale, MCs scale, and leptin/MMP-1 plasma concentration were not positively correlated with HDS. HDS was significantly associated with BMI, leptin IHC score, and MMP-1 IHC score. After a stepwise-multiple linear regression analysis to evaluate the strength of the correlations between HDS and various factors, only the MMP-1 IHC score demonstrated an independent association with HDS in patients with degeneration of the cervical or lumbar disc. CONCLUSIONS MMP-1 IHC score is an independent predictor of the severity of cervical or lumbar IVD degeneration. CLINICAL SIGNIFICANCE MMP-1 IHC score may be used as an indicator of IVD degeneration.
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Affiliation(s)
- Hsien-Ta Hsu
- Division of Neurosurgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; School of Medicine, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Chung-Tai Yue
- Department of Anatomic Pathology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; Department of Pathology, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Ming-Sheng Teng
- Department of Research, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan
| | - I-Shiang Tzeng
- Department of Research, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan
| | - Tin-Chou Li
- Division of Neurosurgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; School of Medicine, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Po-An Tai
- Division of Neurosurgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; School of Medicine, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Kuo-Feng Huang
- Division of Neurosurgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; School of Medicine, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Cheng-Yu Chen
- Department of Family Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan
| | - Yu-Lin Ko
- School of Medicine, Buddhist Tzu Chi University, Hualien, Taiwan; Department of Research, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan.
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Caspase-3 knockout inhibits intervertebral disc degeneration related to injury but accelerates degeneration related to aging. Sci Rep 2019; 9:19324. [PMID: 31852919 PMCID: PMC6920379 DOI: 10.1038/s41598-019-55709-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 12/02/2019] [Indexed: 12/11/2022] Open
Abstract
Approximately 40% of people under 30 and over 90% of people 55 or older suffer from moderate-to-severe levels of degenerative intervertebral disc (IVD) disease in their lumbar spines. Surgical treatments are sometimes effective; however, the treatment of back pain related to IVD degeneration is still a challenge; therefore, new treatments are necessary. Apoptosis may be important in IVD degeneration because suppressing cell apoptosis inside the IVD inhibits degeneration. Caspase-3, the primary effector of apoptosis, may be a key treatment target. We analyzed caspase-3’s role in two different types of IVD degeneration using caspase-3 knockout (Casp-3 KO) mice. Casp-3 KO delayed IVD degeneration in the injury-induced model but accelerated it in the age-induced model. Our results suggest that this is due to different pathological mechanisms of these two types of IVD degeneration. Apoptosis was suppressed in the IVD cells of Casp-3 KO mice, but cellular senescence was enhanced. This would explain why the Casp-3 KO was effective against injury-induced, but not age-related, IVD degeneration. Our results suggest that short-term caspase-3 inhibition could be used to treat injury-induced IVD degeneration.
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Wei Y, Tower RJ, Tian Z, Mohanraj B, Mauck RL, Qin L, Zhang Y. Spatial distribution of type II collagen gene expression in the mouse intervertebral disc. JOR Spine 2019; 2:e1070. [PMID: 31891119 PMCID: PMC6920692 DOI: 10.1002/jsp2.1070] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/19/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023] Open
Abstract
Genetic tools such as the Cre-Lox reporter system are powerful aids for tissue-specific cell tracking. For example, it would be useful in examining intervertebral disc (IVD) cell populations in normal and diseased states. A Cre recombinase and its recognition site, loxP have been adapted from the bacteriophage for use in genetic manipulation. The reporter mice used here express the red fluorescent protein, tdTomato with flanking LoxP sites (Rosa26 TdTomato mice). We compared two different Collagen type II (Col2) promoter constructs that drive Cre-recombinase expression in mice: (a) Col2-Cre, which allows constitutive Cre-recombinase expression under the control of the Col2 promoter/enhancer and (b) Col2-CreER, which contains a shorter promoter/enhancer region than Col2-Cre, but has human estrogen binding elements that bind tamoxifen, resulting in Cre-recombinase expression. The goal of the study is to characterize Cre-recombinase distribution pattern in Col2-Cre and Col2-CreER mice using tdTomato as reporter in the spine. The expression patterns of these two mice were further compared with Col2 gene expression in the native mouse NP and AF tissues by real-time PCR. We crossed Col2-Cre mice or Col2-CreER mice with the tdTomato reporter mice, and compared the tdTomato expression patterns. Col2-CreER/tdTomato mice were injected with tamoxifen at postnatal day 7 to activate the Cre-recombinase. TdTomato in the constitutively active Col2-Cre mice was detected in the nucleus pulposus (NP), the entire annulus fibrosus (AF), and in cartilaginous endplate and growth plate cells in the lower lumbar and coccygeal spine. In contrast, when Col2-CreER activity was induced by tamoxifen at P7, tdTomato was limited to the inner AF, and was absent from the NP. We have described the differences in Col2 reporter gene expression, in Col2-Cre/tdTomato and Col2-Cre-ER/tdTomato mouse IVD. The information provided here will help to guide future investigations of IVD biology.
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Affiliation(s)
- Yulong Wei
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
- Department of OrthopaedicsUnion Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Robert J. Tower
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
| | - Zuozhen Tian
- Department of Physical Medicine and Rehabilitation, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
| | - Bhavana Mohanraj
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
| | - Robert L. Mauck
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
- Department of Physical Medicine and Rehabilitation, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
- Translational Musculoskeletal Research Center (TMRC)Corporal Michael J. Crescenz Veterans Affairs Medical CenterPhiladelphiaPennsylvania
| | - Ling Qin
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
| | - Yejia Zhang
- Department of Orthopaedic Surgery, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
- Department of Physical Medicine and Rehabilitation, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA
- Translational Musculoskeletal Research Center (TMRC)Corporal Michael J. Crescenz Veterans Affairs Medical CenterPhiladelphiaPennsylvania
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Ashinsky BG, Gullbrand SE, Bonnevie ED, Mandalapu SA, Wang C, Elliott DM, Han L, Mauck RL, Smith HE. Multiscale and multimodal structure-function analysis of intervertebral disc degeneration in a rabbit model. Osteoarthritis Cartilage 2019; 27:1860-1869. [PMID: 31419488 PMCID: PMC6875634 DOI: 10.1016/j.joca.2019.07.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/11/2019] [Accepted: 07/18/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVES The objective of this study was to perform a quantitative analysis of the structural and functional alterations in the intervertebral disc during in vivo degeneration, using emerging tools that enable rigorous assessment from the microscale to the macroscale, as well as to correlate these outcomes with noninvasive, clinically relevant imaging parameters. DESIGN Degeneration was induced in a rabbit model by puncturing the annulus fibrosus (AF) with a 16-gauge needle. 2, 4, 8, and 12 weeks following puncture, degenerative changes in the discs were evaluated via magnetic resonance imaging (MRI), whole motion segment biomechanics, atomic force microscopy, histology and polarized light microscopy, immunohistochemistry, biochemical content, and second harmonic generation imaging. RESULTS Following puncture, degeneration was evident through marked changes in whole disc structure and mechanics. Puncture acutely compromised disc macro and microscale mechanics, followed by progressive stiffening and remodeling. Histological analysis showed substantial anterior fibrotic remodeling and osteophyte formation, as well as an overall reduction in disc height, and disorganization and infolding of the AF lamellae into the NP space. Increases in NP collagen content and aggrecan breakdown products were also noted within 4 weeks. On MRI, NP T2 was reduced at all post-puncture time points and correlated significantly with microscale indentation modulus. CONCLUSION This study defined the time dependent changes in disc structure-function relationships during IVD degeneration in a rabbit annular injury model and correlated degeneration severity with clinical imaging parameters. Our findings identified AF infolding and occupancy of the space as a principle mechanism of disc degeneration in response to needle puncture, and provide new insights to direct the development of novel therapeutics.
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Affiliation(s)
- Beth G. Ashinsky
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Drexel University School of Biomedical Engineering, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Sarah E. Gullbrand
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Edward D. Bonnevie
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Sai A. Mandalapu
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Chao Wang
- Drexel University School of Biomedical Engineering, Philadelphia, PA
| | - Dawn M. Elliott
- Department of Biomedical Engineering, University of Delaware, Newark, DE
| | - Lin Han
- Drexel University School of Biomedical Engineering, Philadelphia, PA
| | - Robert L. Mauck
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Harvey E. Smith
- Department of Orthopaedic Surgery, McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA,Address correspondence to: Harvey E. Smith, University of Pennsylvania School of Medicine, Department of Orthopaedic Surgery, 3737 Market Street, 6 Floor, Philadelphia, PA 19104, T: 215-662-3340,
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Aberrant mechanosensing in injured intervertebral discs as a result of boundary-constraint disruption and residual-strain loss. Nat Biomed Eng 2019; 3:998-1008. [PMID: 31611678 PMCID: PMC6899202 DOI: 10.1038/s41551-019-0458-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 08/28/2019] [Indexed: 12/21/2022]
Abstract
In fibrous tissues, pre-stressed boundary constraints at bone interfaces instil residual strain throughout the tissue, even when unloaded. For example, internal swelling pressures in the central nucleus pulposus of the intervertebral disc generate pre-strain in the outer annulus fibrosus. With injury and depressurization, these residual strains are lost. Here, we show that the loss of residual strains in the intervertebral disc alters the microenvironment and instigates aberrant tissue remodelling and the adoption of atypical cellular phenotypes. By using puncture surgery of the annulus fibrosus in rabbits, ex vivo puncture experiments, and electrospun nanofibrous scaffolds recapitulating evolving boundary constraints, we show that the loss of residual strain promotes short-term apoptosis and the emergence of a fibrotic phenotype, that local fibre organization and cellular contractility mediate this process, and that the aberrant cellular changes could be abrogated by targeting the cell-mechanosensing machinery with small molecules. Our findings indicate that injury to dense connective tissues under pre-strain alters boundary constraints and residual strain, leading to aberrant mechanosensing, which in turn promotes disease progression.
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