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Chen ZX, Xu B, Huang ZL, Liu YJ, Li YW, Lu BJ, Lin J, Zhang XD, Shen XF. Causal relationship between systemic circulatory inflammatory regulators and intervertebral disc degeneration: A bidirectional 2-sample Mendelian randomization study. Medicine (Baltimore) 2024; 103:e39521. [PMID: 39252217 PMCID: PMC11384059 DOI: 10.1097/md.0000000000039521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/11/2024] Open
Abstract
In the context of the development of intervertebral disc degeneration (IDD), inflammatory mediators play a pivotal role. Nevertheless, due to the influence of the inflammatory microenvironment, the causal relationship between specific inflammatory mediators and the development of IDD remains uncertain. The understanding of the causal relationship between inflammatory mediators and IDD is of great importance in preventing and delaying disc degeneration in the future. We utilized genetic data concerning systemic circulating inflammatory regulators obtained from a Genome-Wide Association Study (GWAS) analyzing 41 serum cytokines in a cohort of 8293 individuals from Finland. The genetic data for IDD were derived from the most recent GWAS summary statistics conducted within the FinnGen consortium, encompassing 37,636 IDD cases and 270,964 controls. Our analysis employed bidirectional 2-sample Mendelian randomization (MR) techniques, which included several MR methods such as MR Egger, weighted median, inverse variance weighted, weighted mode, and simple mode. Additionally, the MR-PRESSO method was employed to identify horizontal pleiotropy, heterogeneity was quantified using the Cochran Q statistic, and MR-Egger intercept analysis was performed to assess pleiotropy. We established causal relationships between 3 specific inflammatory factors and IDD. Elevated levels of MIP-1β (OR = 0.956, 95% CI: -0.08 to -0.006; P = .02) and IFN-G (OR = 0.915, 95% CI: -0.16 to -0.02; P = .01) expression were associated with a reduced risk of IDD. Conversely, genetic susceptibility to IDD was linked to a decrease in IL-13 levels (OR = 0.967, 95% CI: -0.063 to -0.004; P = .03). In this study, we have identified inflammatory factors that exhibit a causal relationship with the onset and progression of IDD, as supported by genetic predictions.
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Affiliation(s)
- Zi-Xuan Chen
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Bo Xu
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
| | - Ze-Ling Huang
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Yu-Jiang Liu
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
| | - Yu-Wei Li
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
| | - Bin-Jie Lu
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
| | - Jun Lin
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Xian-Da Zhang
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
- Anhui University of Chinese Medicine, Hefei, Anhui, China
| | - Xiao-Feng Shen
- Department of Orthopedics, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, China
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Ambrosio L, Schol J, Ruiz-Fernández C, Tamagawa S, Joyce K, Nomura A, de Rinaldis E, Sakai D, Papalia R, Vadalà G, Denaro V. Getting to the Core: Exploring the Embryonic Development from Notochord to Nucleus Pulposus. J Dev Biol 2024; 12:18. [PMID: 39051200 PMCID: PMC11270426 DOI: 10.3390/jdb12030018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 06/12/2024] [Accepted: 07/02/2024] [Indexed: 07/27/2024] Open
Abstract
The intervertebral disc (IVD) is the largest avascular organ of the human body and plays a fundamental role in providing the spine with its unique structural and biomechanical functions. The inner part of the IVD contains the nucleus pulposus (NP), a gel-like tissue characterized by a high content of type II collagen and proteoglycans, which is crucial for the disc's load-bearing and shock-absorbing properties. With aging and IVD degeneration (IDD), the NP gradually loses its physiological characteristics, leading to low back pain and additional sequelae. In contrast to surrounding spinal tissues, the NP presents a distinctive embryonic development since it directly derives from the notochord. This review aims to explore the embryology of the NP, emphasizing the pivotal roles of key transcription factors, which guide the differentiation and maintenance of the NP cellular components from the notochord and surrounding sclerotome. Through an understanding of NP development, we sought to investigate the implications of the critical developmental aspects in IVD-related pathologies, such as IDD and the rare malignant chordomas. Moreover, this review discusses the therapeutic strategies targeting these pathways, including the novel regenerative approaches leveraging insights from NP development and embryology to potentially guide future treatments.
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Affiliation(s)
- Luca Ambrosio
- Operative Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (L.A.); (R.P.); (V.D.)
- Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 01128 Rome, Italy;
- Department of Orthopaedic Surgery, Tokai University School of Medicine, Isehara 259-1143, Japan; (J.S.); (C.R.-F.); (A.N.); (D.S.)
| | - Jordy Schol
- Department of Orthopaedic Surgery, Tokai University School of Medicine, Isehara 259-1143, Japan; (J.S.); (C.R.-F.); (A.N.); (D.S.)
| | - Clara Ruiz-Fernández
- Department of Orthopaedic Surgery, Tokai University School of Medicine, Isehara 259-1143, Japan; (J.S.); (C.R.-F.); (A.N.); (D.S.)
| | - Shota Tamagawa
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
| | - Kieran Joyce
- CÚRAM, SFI Research Centre for Medical Devices, University of Galway, H91 W2TY Galway, Ireland;
- School of Medicine, University of Galway, H91 W2TY Galway, Ireland
| | - Akira Nomura
- Department of Orthopaedic Surgery, Tokai University School of Medicine, Isehara 259-1143, Japan; (J.S.); (C.R.-F.); (A.N.); (D.S.)
| | - Elisabetta de Rinaldis
- Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 01128 Rome, Italy;
| | - Daisuke Sakai
- Department of Orthopaedic Surgery, Tokai University School of Medicine, Isehara 259-1143, Japan; (J.S.); (C.R.-F.); (A.N.); (D.S.)
| | - Rocco Papalia
- Operative Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (L.A.); (R.P.); (V.D.)
- Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 01128 Rome, Italy;
| | - Gianluca Vadalà
- Operative Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (L.A.); (R.P.); (V.D.)
- Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 01128 Rome, Italy;
| | - Vincenzo Denaro
- Operative Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (L.A.); (R.P.); (V.D.)
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Li Y, Zhang H, Zhu D, Yang F, Wang Z, Wei Z, Yang Z, Jia J, Kang X. Notochordal cells: A potential therapeutic option for intervertebral disc degeneration. Cell Prolif 2024; 57:e13541. [PMID: 37697480 PMCID: PMC10849793 DOI: 10.1111/cpr.13541] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/08/2023] [Accepted: 08/21/2023] [Indexed: 09/13/2023] Open
Abstract
Intervertebral disc degeneration (IDD) is a prevalent musculoskeletal degenerative disorder worldwide, and ~40% of chronic low back pain cases are associated with IDD. Although the pathogenesis of IDD remains unclear, the reduction in nucleus pulposus cells (NPCs) and degradation of the extracellular matrix (ECM) are critical factors contributing to IDD. Notochordal cells (NCs), derived from the notochord, which rapidly degrades after birth and is eventually replaced by NPCs, play a crucial role in maintaining ECM homeostasis and preventing NPCs apoptosis. Current treatments for IDD only provide symptomatic relief, while lacking the ability to inhibit or reverse its progression. However, NCs and their secretions possess anti-inflammatory properties and promote NPCs proliferation, leading to ECM formation. Therefore, in recent years, NCs therapy targeting the underlying cause of IDD has emerged as a novel treatment strategy. This article provides a comprehensive review of the latest research progress on NCs for IDD, covering their biological characteristics, specific markers, possible mechanisms involved in IDD and therapeutic effects. It also highlights significant future directions in this field to facilitate further exploration of the pathogenesis of IDD and the development of new therapies based on NCs strategies.
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Affiliation(s)
- Yanhu Li
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Haijun Zhang
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
- The Second People's Hospital of Gansu ProvinceLanzhouPeople's Republic of China
| | - Daxue Zhu
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Fengguang Yang
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Zhaoheng Wang
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Ziyan Wei
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Zhili Yang
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Jingwen Jia
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
| | - Xuewen Kang
- Lanzhou University Second HospitalLanzhouPeople's Republic of China
- Orthopaedics Key Laboratory of Gansu ProvinceLanzhouPeople's Republic of China
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Chen X, Wang Z, Deng R, Yan H, Liu X, Kang R. Intervertebral disc degeneration and inflammatory microenvironment: expression, pathology, and therapeutic strategies. Inflamm Res 2023; 72:1811-1828. [PMID: 37665342 DOI: 10.1007/s00011-023-01784-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 08/09/2023] [Indexed: 09/05/2023] Open
Abstract
BACKGROUND Intervertebral disc degeneration (IDD) is a leading cause of low back pain (LBP), posing a significant socioeconomic burden. Recent studies highlight the crucial role of inflammatory microenvironment in IDD progression. METHOD A keyword-based search was performed using the PubMed database for published articles. RESULTS AND CONCLUSIONS Dysregulated expression of inflammatory cytokines disrupts intervertebral disc (IVD) homeostasis, causing atrophy, fibrosis, and phenotypic changes in nucleus pulposus cells. Modulating the inflammatory microenvironment and restoring cytokine balance hold promise for IVD repair and regeneration. This comprehensive review systematically examines the expression regulation, pathological effects, therapeutic strategies, and future challenges associated with the inflammatory microenvironment and relevant cytokines in IDD. Key inflammatory cytokines, including interleukins (IL), tumor necrosis factor-alpha (TNF-α), and chemokines, exhibit significant pathological effects in IDD. Furthermore, major therapeutic modalities such as chemical antagonists, biologics, plant extracts, and gene transcription therapies are introduced to control and ameliorate the inflammatory microenvironment. These approaches provide valuable insights for identifying potential targets in future anti-inflammatory treatments for IDD.
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Affiliation(s)
- Xin Chen
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China
| | - Zihan Wang
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China
| | - Rongrong Deng
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China
| | - Hongjie Yan
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China
| | - Xin Liu
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China.
| | - Ran Kang
- The Third Clinical Medical College, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China.
- Department of Orthopedics, Nanjing Lishui Hospital of Traditional Chinese Medicine, Nanjing, 210028, Jiangsu, People's Republic of China.
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5
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Bach FC, Poramba-Liyanage DW, Riemers FM, Guicheux J, Camus A, Iatridis JC, Chan D, Ito K, Le Maitre CL, Tryfonidou MA. Notochordal Cell-Based Treatment Strategies and Their Potential in Intervertebral Disc Regeneration. Front Cell Dev Biol 2022; 9:780749. [PMID: 35359916 PMCID: PMC8963872 DOI: 10.3389/fcell.2021.780749] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/15/2021] [Indexed: 12/20/2022] Open
Abstract
Chronic low back pain is the number one cause of years lived with disability. In about 40% of patients, chronic lower back pain is related to intervertebral disc (IVD) degeneration. The standard-of-care focuses on symptomatic relief, while surgery is the last resort. Emerging therapeutic strategies target the underlying cause of IVD degeneration and increasingly focus on the relatively overlooked notochordal cells (NCs). NCs are derived from the notochord and once the notochord regresses they remain in the core of the developing IVD, the nucleus pulposus. The large vacuolated NCs rapidly decline after birth and are replaced by the smaller nucleus pulposus cells with maturation, ageing, and degeneration. Here, we provide an update on the journey of NCs and discuss the cell markers and tools that can be used to study their fate and regenerative capacity. We review the therapeutic potential of NCs for the treatment of IVD-related lower back pain and outline important future directions in this area. Promising studies indicate that NCs and their secretome exerts regenerative effects, via increased proliferation, extracellular matrix production, and anti-inflammatory effects. Reports on NC-like cells derived from embryonic- or induced pluripotent-stem cells claim to have successfully generated NC-like cells but did not compare them with native NCs for phenotypic markers or in terms of their regenerative capacity. Altogether, this is an emerging and active field of research with exciting possibilities. NC-based studies demonstrate that cues from developmental biology can pave the path for future clinical therapies focused on regenerating the diseased IVD.
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Affiliation(s)
- Frances C. Bach
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | | | - Frank M. Riemers
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Jerome Guicheux
- UMR 1229-RMeS, Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, Nantes, France
- UFR Odontologie, Université de Nantes, Nantes, France
- PHU4 OTONN, CHU Nantes, Nantes, France
| | - Anne Camus
- UMR 1229-RMeS, Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, Nantes, France
| | - James C. Iatridis
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Danny Chan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Keita Ito
- Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
- Department of Orthopedics, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Christine L. Le Maitre
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, United Kingdom
| | - Marianna A. Tryfonidou
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
- *Correspondence: Marianna A. Tryfonidou,
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Kim JH, Ham CH, Kwon WK. Current Knowledge and Future Therapeutic Prospects in Symptomatic Intervertebral Disc Degeneration. Yonsei Med J 2022; 63:199-210. [PMID: 35184422 PMCID: PMC8860939 DOI: 10.3349/ymj.2022.63.3.199] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 11/27/2022] Open
Abstract
Intervertebral disc (IVD) degeneration is the main source of intractable lower back pain, and symptomatic IVD degeneration could be due to different degeneration mechanisms. In this article, we describe the molecular basis of symptomatic IVD degenerative disc diseases (DDDs), emphasizing the role of degeneration, inflammation, angiogenesis, and extracellular matrix (ECM) regulation during this process. In symptomatic DDD, pro-inflammatory mediators modulate catabolic reactions, resulting in changes in ECM homeostasis and, finally, neural/vascular ingrowth-related chronic intractable discogenic pain. In ECM homeostasis, anabolic protein-regulating genes show reduced expression and changes in ECM production, while matrix metalloproteinase gene expression increases and results in aggressive ECM degradation. The resultant loss of normal IVD viscoelasticity and a concomitant change in ECM composition are key mechanisms in DDDs. During inflammation, a macrophage-related cascade is represented by the secretion of high levels of pro-inflammatory cytokines, which induce inflammation. Aberrant angiogenesis is considered a key initiative pathologic step in symptomatic DDD. In reflection of angiogenesis, vascular endothelial growth factor expression is regulated by hypoxia-inducible factor-1 in the hypoxic conditions of IVDs. Furthermore, IVD cells undergoing degeneration potentially enhance neovascularization by secreting large amounts of angiogenic cytokines, which penetrate the IVD from the outer annulus fibrosus, extending deep into the outer part of the nucleus pulposus. Based on current knowledge, a multi-disciplinary approach is needed in all aspects of spinal research, starting from basic research to clinical applications, as this will provide information regarding treatments for DDDs and discogenic pain.
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Affiliation(s)
- Joo Han Kim
- Department of Neurosurgery, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Chang Hwa Ham
- Department of Neurosurgery, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Woo-Keun Kwon
- Department of Neurosurgery, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
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Kirnaz S, Capadona C, Wong T, Goldberg JL, Medary B, Sommer F, McGrath LB, Härtl R. Fundamentals of Intervertebral Disc Degeneration. World Neurosurg 2021; 157:264-273. [PMID: 34929784 DOI: 10.1016/j.wneu.2021.09.066] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 12/16/2022]
Abstract
Lumbar disc degeneration is one of the leading causes of chronic low back pain. The degenerative cascade is often initiated by an imbalance between catabolic and anabolic processes in the intervertebral discs. As a consequence of extracellular matrix degradation, neoinnervation and neovascularization take place. Ultimately, this degenerative process results in disc bulging and loss of nucleus pulposus and water content and subsequent loss of disc height. Most patients respond to conservative management and surgical interventions well initially, yet a significant number of patients continue to suffer from chronic low back pain. Because of the high prevalence of long-term discogenic pain, regenerative biological therapies, including gene therapies, growth factors, cellular-based injections, and tissue-engineered constructs, have attracted significant attention in light of their potential to directly address the degenerative process. Understanding the pathophysiology of degenerative disc disease is important in both refining existing technologies and developing innovative techniques to reverse the degenerative processes in the discs. In this review, we aimed to cover the underlying pathophysiology of degenerative disc disease as well as its associated risk factors and give a comprehensive summary about the developmental, structural, radiological, and biomechanical properties of human intervertebral discs.
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Affiliation(s)
- Sertac Kirnaz
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Charisse Capadona
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Taylor Wong
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Jacob L Goldberg
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Branden Medary
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Fabian Sommer
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Lynn B McGrath
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Brain and Spine Center, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, New York, USA.
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Levillain A, Ahmed S, Kaimaki DM, Schuler S, Barros S, Labonte D, Iatridis J, Nowlan N. Prenatal muscle forces are necessary for vertebral segmentation and disc structure, but not for notochord involution in mice. Eur Cell Mater 2021; 41:558-575. [PMID: 34021906 PMCID: PMC8268087 DOI: 10.22203/ecm.v041a36] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Embryonic muscle forces are necessary for normal vertebral development and spinal curvature, but their involvement in intervertebral disc (IVD) development remains unclear. The aim of the current study was to determine how muscle contractions affect (1) notochord involution and vertebral segmentation, and (2) IVD development including the mechanical properties and morphology, as well as collagen fibre alignment in the annulus fibrosus. Muscular dysgenesis (mdg) mice were harvested at three prenatal stages: at Theiler Stage (TS)22 when notochord involution starts, at TS24 when involution is complete, and at TS27 when the IVD is formed. Vertebral and IVD development were characterised using histology, immunofluorescence, and indentation testing. The results revealed that notochord involution and vertebral segmentation occurred independently of muscle contractions between TS22 and TS24. However, in the absence of muscle contractions, we found vertebral fusion in the cervical region at TS27, along with (i) a displacement of the nucleus pulposus towards the dorsal side, (ii) a disruption of the structural arrangement of collagen in the annulus fibrosus, and (iii) an increase in viscous behaviour of the annulus fibrosus. These findings emphasise the important role of mechanical forces during IVD development, and demonstrate a critical role of muscle loading during development to enable proper annulus fibrosus formation. They further suggest a need for mechanical loading in the creation of fibre-reinforced tissue engineering replacement IVDs as a therapy for IVD degeneration.
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Affiliation(s)
- A. Levillain
- Department of Bioengineering, Imperial College London, London, UK,Université de Lyon, Université Claude Bernard Lyon 1, INSERM, LYOS UMR 1033, Lyon, France
| | - S. Ahmed
- Department of Bioengineering, Imperial College London, London, UK
| | - D-M. Kaimaki
- Department of Bioengineering, Imperial College London, London, UK
| | - S. Schuler
- Department of Bioengineering, Imperial College London, London, UK
| | - S. Barros
- Department of Bioengineering, Imperial College London, London, UK
| | - D. Labonte
- Department of Bioengineering, Imperial College London, London, UK
| | - J.C. Iatridis
- Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - N.C. Nowlan
- Department of Bioengineering, Imperial College London, London, UK,School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland,UCD Conway Institute, University College Dublin, Dublin, Ireland,Address for correspondence: Niamh C. Nowlan, Department of Bioengineering, Imperial College London, London SW72AZ, UK. Telephone number: +44 2075945189
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Ulinastatin Ameliorates IL-1 β-Induced Cell Dysfunction in Human Nucleus Pulposus Cells via Nrf2/NF- κB Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:5558687. [PMID: 33968294 PMCID: PMC8084647 DOI: 10.1155/2021/5558687] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/05/2021] [Accepted: 04/09/2021] [Indexed: 02/08/2023]
Abstract
Low back pain (LBP) has been a wide public health concern worldwide. Among the pathogenic factors, intervertebral disc degeneration (IDD) has been one of the primary contributors to LBP. IDD correlates closely with inflammatory response and oxidative stress, involving a variety of inflammation-related cytokines, such as interleukin 1 beta (IL-1β), which could result in local inflammatory environment. Ulinastatin (UTI) is a kind of acidic protein extracted from human urine, which inhibits the release of tumor necrosis factor alpha (TNF-α) and other inflammatory factors to protect organs from inflammatory damage. However, whether this protective effect of UTI on human nucleus pulposus (NP) exists, and how UTI affects the biological behaviors of human NP cells during IDD remain elusive. In this current study, we revealed that UTI could improve the viability of NP cells and promote the proliferation of NP cells. Additionally, UTI could protect human NP cells via ameliorating IL-1β-induced apoptosis, inflammatory response, oxidative stress, and extracellular matrix (ECM) degradation. Molecular mechanism analysis suggested that the protective effect from UTI on IL-1β-treated NP cells were through activating nuclear factor- (erythroid-derived 2-) like 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway and the suppression of NF-κB signaling pathway. Therefore, UTI may be a promising therapeutic medicine to ameliorate IDD.
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10
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Abstract
The complex structure of the intervertebral disc within the spine is well suited to its mechanical function. However, it is also prone to degeneration, which is associated with various clinical symptoms and conditions, ranging from disc herniation to back pain to spinal stenosis. Most patients' conditions are managed conservatively but a small proportion progress to having surgery. This may be decompression (to remove tissue such as the disc, bone, or hypertrophic ligaments impinging on nerves) or fusion of the normally mobile intervertebral joint to immobilize it and so reduce pain. These used to involve fairly major surgical procedures, but in the past decade there has been much progress to make the surgery more refined and less invasive, for example using endoscopic approaches. Simultaneously, the research world has been studying and developing tissue engineering and cellular techniques for attempting to regenerate the intervertebral disc, whether simply the central nucleus pulposus or a complete intricate assembly to replicate the native structure of this and the surrounding annulus fibrosus, cartilage endplate, and bone. To date, none of the complex entities have been trialed, while cellular approaches are easier to utilize, have progressed to clinical trials, and may offer a better solution.
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Affiliation(s)
- Stephen M Eisenstein
- Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Oswestry, Shropshire, UK
- School of Pharmacy and Bioengineering, Keele University, Keele, Staffordshire, UK
| | - Birender Balain
- Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Oswestry, Shropshire, UK
| | - Sally Roberts
- Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Oswestry, Shropshire, UK
- School of Pharmacy and Bioengineering, Keele University, Keele, Staffordshire, UK
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11
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Tang S, Richards J, Khan S, Hoyland J, Gallego-Perez D, Higuita-Castro N, Walter B, Purmessur D. Nonviral Transfection With Brachyury Reprograms Human Intervertebral Disc Cells to a Pro-Anabolic Anti-Catabolic/Inflammatory Phenotype: A Proof of Concept Study. J Orthop Res 2019; 37:2389-2400. [PMID: 31286562 DOI: 10.1002/jor.24408] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/25/2019] [Indexed: 02/04/2023]
Abstract
Intervertebral disc (IVD) degeneration is a major contributor to chronic low back pain and is characterized by decreases in cellularity and proteoglycan synthesis, upregulation of matrix degradation, and increases in pro-inflammatory factors with neurovascular invasion. Current treatments fail to target the underlying pathology or promote tissue repair and approaches such as viral transfection raise safety concerns due to mutagenesis and unwarranted immune responses. To avoid such concerns, nonviral transfection is a viable method of gene delivery into the host cell while bypassing the caveats of viral delivery. Brachyury is expressed in the developing notochord and is associated with an immature healthy nucleus pulposus (NP). We hypothesize that Brachyury can reprogram degenerate NP cells to a healthy pro-anabolic phenotype with increased proteoglycan content and decreased expression of catabolic, inflammatory, and neurovascular markers. NP cells obtained from human autopsy and surgical tissues were transfected with plasmids encoding for Brachyury or an empty vector control via bulk electroporation. Post transfection, cells were seeded in three-dimensional agarose constructs cultured over 4 weeks and analyzed for viability, gene expression, and proteoglycan. Results demonstrated successful transfection of both autopsy and surgical NP cells. We observed long-term Brachyury expression, significant increased expression of NP phenotypic markers FOXF1, KRT19, and chondrogenic marker SOX9 with decreases in inflammatory cytokines IL1-β/IL6, NGF, and MMPs and significant increases in glycosaminoglycan accumulation. These results highlight nonviral transfection with developmental transcription factors, such as Brachyury, as a promising method to reprogram degenerate human disc cells toward a healthy NP phenotype. Clinical significance: This project proposes a novel translational approach for the treatment of intervertebral disc degeneration via direct reprogramming of diseased human patient-derived IVD cells to a healthy phenotype. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2389-2400, 2019.
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Affiliation(s)
- Shirley Tang
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Justin Richards
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Safdar Khan
- Department of Orthopedics, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Judith Hoyland
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, The University of Manchester, Manchester, United Kingdom.,NIHR Manchester Musculoskeletal Biomedical Research Centre, NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester University, Manchester, United Kingdom
| | | | | | - Benjamin Walter
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Devina Purmessur
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio.,Department of Orthopedics, The Ohio State University Wexner Medical Center, Columbus, Ohio
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12
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Richards J, Tang S, Gunsch G, Sul P, Wiet M, Flanigan DC, Khan SN, Moore S, Walter B, Purmessur D. Mast Cell/Proteinase Activated Receptor 2 (PAR2) Mediated Interactions in the Pathogenesis of Discogenic Back Pain. Front Cell Neurosci 2019; 13:294. [PMID: 31333416 PMCID: PMC6625229 DOI: 10.3389/fncel.2019.00294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/17/2019] [Indexed: 12/19/2022] Open
Abstract
Mast cells (MCs) are present in the painful degenerate human intervertebral disc (IVD) and are associated with disease pathogenesis. MCs release granules containing enzymatic and inflammatory factors in response to stimulants or allergens. The serine protease, tryptase, is unique to MCs and its activation of the G-protein coupled receptor, Protease Activated Receptor 2 (PAR2), induces inflammation and degradation in osteoarthritic cartilage. Our previously published work has demonstrated increased levels of MC marker tryptase in IVD samples from discogenic back pain patients compared to healthy control IVD samples including expression of chemotactic agents that may facilitate MC migration into the IVD. To further elucidate MCs’ role in the IVD and mechanisms underlying its effects, we investigated whether (1) human IVD cells can promote MC migration, (2) MC tryptase can mediate up-regulation of inflammatory/catabolic process in human IVD cells and tissue, and (3) the potential of PAR2 antagonist to function as a therapeutic drug in in vitro human and ex vivo bovine pilot models of disease. MC migration was quantitatively assessed using conditioned media from primary human IVD cells and MC migration examined through Matrigel. Exposure to soluble IVD factors significantly enhanced MC migration, suggesting IVD cells can recruit MCs. We also demonstrated significant upregulation of MC chemokine SCF and angiogenic factor VEGFA gene expression in human IVD cells in vitro in response to recombinant human tryptase, suggesting tryptase can enhance recruitment of MCs and promotion of angiogenesis into the usually avascular IVD. Furthermore, tryptase can degrade proteoglycans in IVD tissue as demonstrated by significant increases in glycosaminoglycans released into surrounding media. This can create a catabolic microenvironment compromising structural integrity and facilitating vascular migration usually inhibited by the anti-angiogenic IVD matrix. Finally, as a “proof of concept” study, we examined the therapeutic potential of PAR2 antagonist (PAR2A) on human IVD cells and bovine organ culture IVD model. While preliminary data shows promise and points toward structural restoration of the bovine IVD including down-regulation of VEGFA, effects of PAR2 antagonist on human IVD cells differ between gender and donors suggesting that further validation is required with larger cohorts of human specimens.
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Affiliation(s)
- Justin Richards
- College of Arts and Sciences, The Ohio State University, Columbus, OH, United States
| | - Shirley Tang
- College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Gilian Gunsch
- College of Arts and Sciences, The Ohio State University, Columbus, OH, United States
| | - Pavel Sul
- College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Matthew Wiet
- College of Engineering, The Ohio State University, Columbus, OH, United States
| | - David C Flanigan
- Department of Orthopaedics, Wexner Medical Center, 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
| | - Sarah Moore
- College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Benjamin Walter
- College of Engineering, The Ohio State University, Columbus, OH, United States.,Department of Orthopaedics, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Devina Purmessur
- College of Engineering, The Ohio State University, Columbus, OH, United States.,Department of Orthopaedics, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
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13
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Liu X, Krishnamoorthy D, Lin L, Xue P, Zhang F, Chi L, Linhardt RJ, Iatridis JC. A method for characterising human intervertebral disc glycosaminoglycan disaccharides using liquid chromatography-mass spectrometry with multiple reaction monitoring. Eur Cell Mater 2018; 35:117-131. [PMID: 29469163 PMCID: PMC5865475 DOI: 10.22203/ecm.v035a09] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Intervertebral disc (IVD) degeneration results in the depletion of proteoglycans and glycosaminoglycans (GAGs), which can lead to structural and mechanical loss of IVD function, ingrowth of nociceptive nerve fibres and eventually discogenic pain. Specific GAG types as well as their disaccharide patterns can be predictive of disease and degeneration in several tissues but have not been comprehensively studied within the IVD. A highly sensitive mass spectrometry based technique with multiple reaction monitoring (MRM) was used to provide characterisation of chondroitin sulphate (CS), hyaluronic acid (HA), heparan sulphate (HS) and their disaccharide sulphation patterns across different anatomical regions of human IVDs. Principal component analysis further distinguished important regional variations and proposed potential ageing variations in GAG profiles. CS was the GAG in greatest abundance in the IVD followed by HA and HS. Principal component analysis identified clear separation of GAG profiles between nucleus pulposus and annulus fibrosus in young and old specimens. Distinct patterns of predominantly expressed disaccharides of CS and HS between young and old IVD samples, provided preliminary evidence that important alterations in disaccharides occur within IVDs during ageing. This technique offered a novel approach to identify and quantify specific GAG disaccharides in human IVDs and the data presented were the first to offer insight into the spatial distribution as well as association with ageing of GAGs and GAG disaccharide sulphation patterns across the human IVD.
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Affiliation(s)
| | | | | | | | | | | | | | - J C Iatridis
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, 1 Gustave Levy Place, Box 1188, New York, NY 10029-6574, USA
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14
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Palacio-Mancheno PE, Evashwick-Rogler TW, Laudier DM, Purmessur D, Iatridis JC. Hyperosmolarity induces notochordal cell differentiation with aquaporin3 upregulation and reduced N-cadherin expression. J Orthop Res 2018; 36:788-798. [PMID: 28853179 PMCID: PMC5832547 DOI: 10.1002/jor.23715] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 08/19/2017] [Indexed: 02/04/2023]
Abstract
The nucleus pulposus (NP) of intervertebral discs (IVD) undergoes dramatic changes with aging including loss of its gelatinous structure and large, vacuolated notochordal cells (NCs) in favor of a matrix-rich structure populated by small NP cells (sNPCs). NP maturation also involves a loading-pattern shift from pressurization to matrix deformations, and these events are thought to predispose to degeneration. Little is known of the triggering events and cellular alterations involved with NP maturation, which remains a fundamental open spinal mechanobiology question. A mouse IVD organ culture model was used to test the hypotheses that hyperosmotic overloading will induce NP maturation with transition of NCs to sNPCs while also increasing matrix accumulation and altering osmoregulatory and mechanotransductive proteins. Results indicated that static hyperosmolarity, as might occur during growth, caused maturation of NCs to sNPCs and involved a cellular differentiation process since known NC markers (cytokeratin-8, -19, and sonic hedgehog) persisted without increased cell apoptosis. Osmosensitive channels Aquaporin 3 (Aqp3) and transient receptor potential vanilloid-4 (TRPV4) expression were both modified with altered osmolarity, but increased Aqp3 with hyperosmolarity was associated with NC to sNPC differentiation. NC to sNPC differentiation was accompanied by a shift in cellular mechanotransduction proteins with decreased N-cadherin adhesions and increased Connexin 43 connexons. We conclude that hyperosmotic overloading can promote NC differentiation into sNPCs. This study identified osmolarity as a triggering mechanism for notochordal cell differentiation with associated shifts in osmoregulatory and mechanotransductive proteins that are likely to play important roles in intervertebral disc aging. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:788-798, 2018.
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Affiliation(s)
| | | | - Damien M. Laudier
- Dept. of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Devina Purmessur
- Dept. of Biomedical Engineering, Ohio State University, Columbus, OH
| | - James C. Iatridis
- Dept. of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY
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15
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Notochordal-cell derived extracellular vesicles exert regenerative effects on canine and human nucleus pulposus cells. Oncotarget 2017; 8:88845-88856. [PMID: 29179481 PMCID: PMC5687651 DOI: 10.18632/oncotarget.21483] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 08/26/2017] [Indexed: 12/15/2022] Open
Abstract
During intervertebral disc ageing, chondrocyte-like cells (CLCs) replace notochordal cells (NCs). NCs have been shown to induce regenerative effects in CLCs. Since vesicles released by NCs may be responsible for these effects, we characterized NC-derived extracellular vesicles (EVs) and determined their effect on CLCs. EVs were purified from porcine NC-conditioned medium (NCCM) through size exclusion chromatography, ultracentrifugation or density gradient centrifugation. Additionally, the EVs were quantitatively analyzed by high-resolution flow cytometry. The effect of NCCM-derived EVs was studied on canine and human CLC micro-aggregates in vitro and compared with NCCM-derived proteins and unfractionated NCCM. Porcine NCCM contained a considerable amount of EVs. NCCM-derived EVs induced GAG deposition in canine CLCs to a comparable level as NCCM-derived proteins and unfractionated NCCM, and increased the DNA and glycosaminoglycan (GAG) content of human micro-aggregates, although to a lesser extent than unfractionated NCCM. The biological EV effects were not considerably influenced by ultracentrifugation compared with size exclusion-based purification. Upon ultracentrifugation, interfering GAGs, but not collagens, were lost. Nonetheless, collagen type I or II supplemented to CLCs in a concentration as present in NCCM induced no anabolic effects. Porcine NCCM-derived EVs exerted anabolic effects comparable to NCCM-derived proteins, while unfractionated NCCM was more potent in human CLCs. GAGs and collagens appeared not to mediate the regenerative EV effects. Thus, NC-derived EVs have regenerative potential, and their effects may be influenced by the proteins present in NCCM. The optimal combination of NC-secreted factors needs to be determined to fully exploit the regenerative potential of NC-based technology.
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16
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Kwon WK, Moon HJ, Kwon TH, Park YK, Kim JH. Influence of rabbit notochordal cells on symptomatic intervertebral disc degeneration: anti-angiogenic capacity on human endothelial cell proliferation under hypoxia. Osteoarthritis Cartilage 2017. [PMID: 28647468 DOI: 10.1016/j.joca.2017.06.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVES Symptomatic degenerative disc disease (DDD) is associated with neovascularization and nerve ingrowth into intervertebral discs (IVDs). Notochordal cells (NCs) are key cells that may lead to regeneration of IVDs. However, their activities under conditions of hypoxia, the real environment of IVD, are not well known. We hypothesized that NCs may inhibit neovascularization by interacting with endothelial cells (ECs) under hypoxia. DESIGN Human IVDs were isolated and cultured to produce nucleus pulposus (NP) cell conditioned medium (NPCM). Immortalized human microvascular ECs were cultured in NPCM with notochordal cell-rich rabbit nucleus pulposus cells (rNC) under hypoxia. Vascular endothelial growth factor (VEGF), vascular cell adhesion molecule (VCAM), and interleukin-8 (IL-8) were analyzed by ELISA. Focal adhesion kinase (FAK), filamentous actin (F-actin), and platelet-derived growth factor (PDGF) were evaluated to investigate EC activity. Wound-healing migration assays were performed to examine EC migration. RESULTS The VEGF level of EC cells cultured in NPCM was significantly higher under hypoxia compared to normoxia. VEGF expression was significantly decreased, and FAK, F-actin, PDGF expression were inhibited when ECs were cocultured with rNCs under hypoxia. ECs cocultured with rNC in NPCM showed significantly decreased migratory activity compared to those without rNC under hypoxia. CONCLUSIONS The angiogenic capacity of ECs was significantly inhibited by NCs under hypoxia via a VEGF-related pathway. Our results suggest that NCs may play a key role in the development of IVDs by inhibiting vascular growth within the disc, and this may be a promising novel therapeutic strategy for targeting vascular ingrowth in symptomatic DDD.
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Affiliation(s)
- W-K Kwon
- Department of Neurosurgery, Guro Hospital, College of Medicine, Korea University, Seoul, Republic of Korea.
| | - H J Moon
- Department of Neurosurgery, Guro Hospital, College of Medicine, Korea University, Seoul, Republic of Korea.
| | - T-H Kwon
- Department of Neurosurgery, Guro Hospital, College of Medicine, Korea University, Seoul, Republic of Korea.
| | - Y-K Park
- Department of Neurosurgery, Guro Hospital, College of Medicine, Korea University, Seoul, Republic of Korea.
| | - J H Kim
- Department of Neurosurgery, Guro Hospital, College of Medicine, Korea University, Seoul, Republic of Korea.
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17
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Mosley GE, Evashwick-Rogler TW, Lai A, Iatridis JC. Looking beyond the intervertebral disc: the need for behavioral assays in models of discogenic pain. Ann N Y Acad Sci 2017; 1409:51-66. [PMID: 28797134 DOI: 10.1111/nyas.13429] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/02/2017] [Accepted: 06/12/2017] [Indexed: 12/28/2022]
Abstract
Orthopedic research into chronic discogenic back pain has commonly focused on aging- and degeneration-related changes in intervertebral disc structure, biomechanics, and biology. However, the primary spine-related reason for physician office visits is pain. The ambiguous nature of the human condition of discogenic low back pain motivates the use of animal models to better understand the pathophysiology. Discogenic back pain models must consider both emergent behavioral changes following pain induction and changes in the nervous system that mediate such behavior. Looking beyond the intervertebral disc, we describe the different ways to classify pain in human patients and animal models. We describe several behavioral assays that can be used in rodent models to augment disc degeneration measurements and characterize different types of pain. We review rodent models of discogenic pain that employed behavioral pain assays and highlight a need to better integrate neuroscience and orthopedic science methods to extend current understanding of the complex and multifactorial pathophysiology of discogenic back pain.
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Affiliation(s)
- Grace E Mosley
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Thomas W Evashwick-Rogler
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Alon Lai
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - James C Iatridis
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
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18
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Dowdell J, Erwin M, Choma T, Vaccaro A, Iatridis J, Cho SK. Intervertebral Disk Degeneration and Repair. Neurosurgery 2017; 80:S46-S54. [PMID: 28350945 PMCID: PMC5585783 DOI: 10.1093/neuros/nyw078] [Citation(s) in RCA: 266] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/22/2016] [Indexed: 12/25/2022] Open
Abstract
Intervertebral disk (IVD) degeneration is a natural progression of the aging process. Degenerative disk disease (DDD) is a pathologic condition associated with IVD that has been associated with chronic back pain. There are a variety of different mechanisms of DDD (genetic, mechanical, exposure). Each of these pathways leads to a final common result of unbalancing the anabolic and catabolic environment of the extracellular matrix in favor of catabolism. Attempts have been made to gain an understanding of the process of IVD degeneration with in Vitro studies. These models help our understanding of the disease process, but are limited as they do not come close to replicating the complexities that exist with an in Vivo model. Animal models have been developed to help us gain further understanding of the degenerative cascade of IVD degeneration In Vivo and test experimental treatment modalities to either prevent or reverse the process of DDD. Many modalities for treatment of DDD have been developed including therapeutic protein injections, stem cell injections, gene therapy, and tissue engineering. These interventions have had promising outcomes in animal models. Several of these modalities have been attempted in human trials, with early outcomes having promising results. Further, increasing our understanding of the degenerative process is essential to the development of new therapeutic interventions and the optimization of existing treatment protocols. Despite limited data, biological therapies are a promising treatment modality for DDD that could impact our future management of low back pain.
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Affiliation(s)
- James Dowdell
- Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Mark Erwin
- Department of Orthopedics, University of Toronto, Toronto, Ontario, Canada
| | - Theodoe Choma
- Department of Orthopedics, University of Missouri, Columbia, Missouri
| | - Alexander Vaccaro
- Department of Orthopedics, Rothman Institute, Philadel-phia, Pennsylvania
| | - James Iatridis
- Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Samuel K Cho
- Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, New York
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Gantenbein B, Illien-Jünger S, Chan SCW, Walser J, Haglund L, Ferguson SJ, Iatridis JC, Grad S. Organ culture bioreactors--platforms to study human intervertebral disc degeneration and regenerative therapy. Curr Stem Cell Res Ther 2016; 10:339-52. [PMID: 25764196 DOI: 10.2174/1574888x10666150312102948] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 02/25/2015] [Accepted: 03/01/2015] [Indexed: 12/31/2022]
Abstract
In recent decades the application of bioreactors has revolutionized the concept of culturing tissues and organs that require mechanical loading. In intervertebral disc (IVD) research, collaborative efforts of biomedical engineering, biology and mechatronics have led to the innovation of new loading devices that can maintain viable IVD organ explants from large animals and human cadavers in precisely defined nutritional and mechanical environments over extended culture periods. Particularly in spine and IVD research, these organ culture models offer appealing alternatives, as large bipedal animal models with naturally occurring IVD degeneration and a genetic background similar to the human condition do not exist. Latest research has demonstrated important concepts including the potential of homing of mesenchymal stem cells to nutritionally or mechanically stressed IVDs, and the regenerative potential of "smart" biomaterials for nucleus pulposus or annulus fibrosus repair. In this review, we summarize the current knowledge about cell therapy, injection of cytokines and short peptides to rescue the degenerating IVD. We further stress that most bioreactor systems simplify the real in vivo conditions providing a useful proof of concept. Limitations are that certain aspects of the immune host response and pain assessments cannot be addressed with ex vivo systems. Coccygeal animal disc models are commonly used because of their availability and similarity to human IVDs. Although in vitro loading environments are not identical to the human in vivo situation, 3D ex vivo organ culture models of large animal coccygeal and human lumbar IVDs should be seen as valid alternatives for screening and feasibility testing to augment existing small animal, large animal, and human clinical trial experiments.
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Affiliation(s)
- Benjamin Gantenbein
- Institute for Surgical Technology & Biomechanics, Medical Faculty, University, Stauffacherstrasse 78, CH-3014 Bern, Switzerland.
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20
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Purmessur D, Cornejo MC, Cho SK, Roughley PJ, Linhardt RJ, Hecht AC, Iatridis JC. Intact glycosaminoglycans from intervertebral disc-derived notochordal cell-conditioned media inhibit neurite growth while maintaining neuronal cell viability. Spine J 2015; 15:1060-9. [PMID: 25661435 PMCID: PMC4416992 DOI: 10.1016/j.spinee.2015.02.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 12/08/2014] [Accepted: 02/01/2015] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Painful human intervertebral discs (IVDs) exhibit nerve growth deep into the IVD. Current treatments for discogenic back pain do not address the underlying mechanisms propagating pain and are often highly invasive or only offer temporary symptom relief. The notochord produces factors during development that pattern the spine and inhibit the growth of dorsal root ganglion (DRG) axons into the IVD. We hypothesize that notochordal cell (NC)-conditioned medium (NCCM) includes soluble factors capable of inhibiting neurite growth and may represent a future therapeutic target. PURPOSE To test if NCCM can inhibit neurite growth and determine if NC-derived glycosaminoglycans (GAGs) are necessary candidates for this inhibition. STUDY DESIGN Human neuroblastoma (SH-SY5Y) cells and rat DRG cells were treated with NCCM in two-dimensional culture in vitro, and digestion and mechanistic studies determined if specific GAGs were responsible for inhibitory effects. METHODS Notochordal cell-conditioned medium was generated from porcine nucleus pulposus tissue that was cultured in Dulbecco's modified eagle's medium for 4 days. A dose study was performed using SH-SY5Y cells that were seeded in basal medium for 24 hours and neurite outgrowth and cell viability were assessed after treatment with basal media or NCCM (10% and 100%) for 48 hours. Glycosaminoglycans from NCCM were characterized using multiple digestions and liquid chromatography mass spectroscopy (LC-MS). Neurite growth was assessed on both SH-SY5Y and DRG cells after treatment with NCCM with and without GAG digestion. RESULTS Notochordal cell-conditioned medium significantly inhibited the neurite outgrowth from SH-SY5Y cells compared with basal controls without dose or cytotoxic effects; % of neurite expressing cells were 39.0±2.9%, 27.3±3.6%, and 30.2±2.7% and mean neurite length was 60.3±3.5, 50.8±2.4, 53.2±3.7 μm for basal, 10% NCCM, and 100% NCCM, respectively. Digestions and LC-MS determined that chondroitin-6-sulfate was the major GAG chain in NCCM. Neurite growth from SH-SY5Y and DRG cells was not inhibited when cells were treated with NCCM with digested chondroitin sulfate (CS). CONCLUSIONS Soluble factors derived from NCCM were capable of inhibiting neurite outgrowth in multiple neural cell types without any negative effects on cell viability. Cleavage of GAGs via digestion was necessary to reverse the neurite inhibition capacity of NCCM. We conclude that intact GAGs such as CS secreted from NCs are potential candidates that could be useful to reduce neurite growth in painful IVDs.
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Affiliation(s)
- Devina Purmessur
- Leni & Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Marisa C Cornejo
- Leni & Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Samuel K Cho
- Leni & Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | | | - Robert J Linhardt
- Biocatalysis & Metabolic Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180
| | - Andrew C Hecht
- Leni & Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - James C Iatridis
- Leni & Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, One Gustave L.levy place, box 1188 New York, NY 10029, USA.
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21
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Developments in intervertebral disc disease research: pathophysiology, mechanobiology, and therapeutics. Curr Rev Musculoskelet Med 2015; 8:18-31. [PMID: 25694233 DOI: 10.1007/s12178-014-9253-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Low back pain is a leading cause of disability worldwide and the second most common cause of physician visits. There are many causes of back pain, and among them, disc herniation and intervertebral disc degeneration are the most common diagnoses and targets for intervention. Currently, clinical treatment outcomes are not strongly correlated with diagnoses, emphasizing the importance for characterizing more completely the mechanisms of degeneration and their relationships with symptoms. This review covers recent studies elucidating cellular and molecular changes associated with disc mechanobiology, as it relates to degeneration and regeneration. Specifically, we review findings on the biochemical changes in disc diseases, including cytokines, chemokines, and proteases; advancements in disc disease diagnostics using imaging modalities; updates on studies examining the response of the intervertebral disc to injury; and recent developments in repair strategies, including cell-based repair, biomaterials, and tissue engineering. Findings on the effects of the omega-6 fatty acid, linoleic acid, on nucleus pulposus tissue engineering are presented. Studies described in this review provide greater insights into the pathogenesis of disc degeneration and may define new paradigms for early or differential diagnostics of degeneration using new techniques such as systemic biomarkers. In addition, research on the mechanobiology of disease enriches the development of therapeutics for disc repair, with potential to diminish pain and disability associated with disc degeneration.
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Arkesteijn ITM, Smolders LA, Spillekom S, Riemers FM, Potier E, Meij BP, Ito K, Tryfonidou MA. Effect of coculturing canine notochordal, nucleus pulposus and mesenchymal stromal cells for intervertebral disc regeneration. Arthritis Res Ther 2015; 17:60. [PMID: 25890127 PMCID: PMC4396569 DOI: 10.1186/s13075-015-0569-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 02/19/2015] [Indexed: 12/27/2022] Open
Abstract
Introduction Early degenerative changes in the nucleus pulposus (NP) are observed after the disappearance of notochordal cells (NCs). Thus, it has been suggested that NCs play an important role in maintaining the NP and may have a regenerative potential on other cells of the NP. As the number of resident NP cells (NPCs) decreases in a degenerating disc, mesenchymal stromal (stem) cells (MSCs) may be used for cell supplementation. In this study, using cells of one species, the regenerative potential of canine NCs was assessed in long-term three-dimensional coculture with canine NPCs or MSCs. Methods Canine NCs and canine NPCs or MSCs were cocultured in alginate beads for 28 days under hypoxic and high-osmolarity conditions. Cell viability, cell morphology and DNA content, extracellular matrix production and expression of genes related to NC markers (Brachyury, KRT18) and NP matrix production (ACAN, COL2A1, COL1A1) were assessed after 1, 15 and 28 days of culture. Results NCs did not completely maintain their phenotype (morphology, matrix production, gene expression) during 28 days of culture. In cocultures of NPCs and NCs, both extracellular matrix content and anabolic gene expression remained unchanged compared with monoculture groups, whereas cocultures of MSCs and NCs showed increased glycosaminoglycan/DNA. However, the deposition of these proteoglycans was observed near the NCs and not the MSCs. Brachyury expression in the MSC and NC coculture group increased in time. The latter two findings indicate a trophic effect of MSCs on NCs rather than vice versa. Conclusions No regenerative potential of canine NCs on canine NPCs or MSCs was observed in this study. However, significant changes in NC phenotype in long-term culture may have resulted in a suboptimal regenerative potential of these NCs. In this respect, NC-conditioned medium may be better than coculture for future studies of the regenerative potential of NCs. Electronic supplementary material The online version of this article (doi:10.1186/s13075-015-0569-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Irene T M Arkesteijn
- Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
| | - Lucas A Smolders
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.154, NL-3508 TD, Utrecht, The Netherlands. .,Clinic for Small Animal Surgery, Vetsuisse Faculty, Zurich University, Winterthurerstrasse 260, CH-8057, Zurich, Switzerland.
| | - Sandra Spillekom
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.154, NL-3508 TD, Utrecht, The Netherlands.
| | - Frank M Riemers
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.154, NL-3508 TD, Utrecht, The Netherlands.
| | - Esther Potier
- Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands. .,Laboratoire de Bioingénierie et Biomécanique Ostéo-Articulaire (B2OA), UMR CNRS 7052, Université Denis Diderot Paris 7, Sorbonne Paris Cité, 690, Paris, France.
| | - Björn P Meij
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.154, NL-3508 TD, Utrecht, The Netherlands.
| | - Keita Ito
- Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands. .,Department of Orthopedics, University Medical Center Utrecht, P.O. Box 85500, HP G05.228, 3508 GA, Utrecht, The Netherlands.
| | - Marianna A Tryfonidou
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.154, NL-3508 TD, Utrecht, The Netherlands.
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Cornejo M, Cho S, Giannarelli C, Iatridis J, Purmessur D. Soluble factors from the notochordal-rich intervertebral disc inhibit endothelial cell invasion and vessel formation in the presence and absence of pro-inflammatory cytokines. Osteoarthritis Cartilage 2015; 23:487-96. [PMID: 25534363 PMCID: PMC4411226 DOI: 10.1016/j.joca.2014.12.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 11/11/2014] [Accepted: 12/12/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND Chronic low back pain can be associated with the pathological ingrowth of blood vessels and nerves into intervertebral discs (IVDs). The notochord patterns the IVD during development and is a source of anti-angiogenic soluble factors such as Noggin and Chondroitin sulfate (CS). These factors may form the basis for a new minimally invasive strategy to target angiogenesis in the IVD. OBJECTIVE To examine the anti-angiogenic potential of soluble factors from notochordal cells (NCs) and candidates Noggin and CS under healthy culture conditions and in the presence of pro-inflammatory mediators. DESIGN NC conditioned media (NCCM) was generated from porcine NC-rich nucleus pulposus tissue. To assess the effects of NCCM, CS and Noggin on angiogenesis, cell invasion and tubular formation assays were performed using human umbilical vein endothelial cells (HUVECs) ± tumor necrosis factor alpha (TNFα [10 ng/ml]). vascular endothelial growth factor (VEGF)-A, MMP-7, interleukin-6 (IL-6) and IL-8 mRNA levels were assessed using qRT-PCR. RESULTS NCCM (10 & 100%), CS (10 and 100 μg) and Noggin (10 and 100 ng) significantly decreased cell invasion of HUVECs with and without TNFα. NCCM 10% and Noggin 10 ng inhibited tubular formation with and without TNFα and CS 100 μg inhibited tubules in Basal conditions whereas CS 10 μg inhibited tubules with TNFα. NCCM significantly decreased VEGF-A, MMP-7 and IL-6 mRNA levels in HUVECs with and without TNFα. CS and Noggin had no effects on gene expression. CONCLUSIONS We provide the first evidence that soluble factors from NCs can inhibit angiogenesis by suppressing VEGF signaling. Notochordal-derived ligands are a promising minimally invasive strategy targeting neurovascular ingrowth and pain in the degenerated IVD.
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Affiliation(s)
- M.C. Cornejo
- Leni and Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - S.K. Cho
- Leni and Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - C. Giannarelli
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - J.C. Iatridis
- Leni and Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - D. Purmessur
- Leni and Peter W. May Department of Orthopedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA,Address correspondence and reprint requests to: D. Purmessur, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1188, New York, NY 10029, USA. Tel: 1-212-241-1531
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Gantenbein B, Calandriello E, Wuertz-Kozak K, Benneker LM, Keel MJB, Chan SCW. Activation of intervertebral disc cells by co-culture with notochordal cells, conditioned medium and hypoxia. BMC Musculoskelet Disord 2014; 15:422. [PMID: 25496082 PMCID: PMC4295479 DOI: 10.1186/1471-2474-15-422] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 12/01/2014] [Indexed: 12/14/2022] Open
Abstract
Background Notochordal cells (NC) remain in the focus of research for regenerative therapy for the degenerated intervertebral disc (IVD) due to their progenitor status. Recent findings suggested their regenerative action on more mature disc cells, presumably by the secretion of specific factors, which has been described as notochordal cell conditioned medium (NCCM). The aim of this study was to determine NC culture conditions (2D/3D, fetal calf serum, oxygen level) that lead to significant IVD cell activation in an indirect co-culture system under normoxia and hypoxia (2% oxygen). Methods Porcine NC was kept in 2D monolayer and in 3D alginate bead culture to identify a suitable culture system for these cells. To test stimulating effects of NC, co-cultures of NC and bovine derived coccygeal IVD cells were conducted in a 1:1 ratio with no direct cell contact between NC and bovine nucleus pulposus cell (NPC) or annulus fibrosus cells (AFC) in 3D alginate beads under normoxia and hypoxia (2%) for 7 and 14 days. As a positive control, NPC and AFC were stimulated with NC-derived conditioned medium (NCCM). Cell activity, glycosaminoglycan (GAG) content, DNA content and relative gene expression was measured. Mass spectrometry analysis of the NCCM was conducted. Results We provide evidence by flow cytometry that monolayer culture is not favorable for NC culture with respect to maintaining NC phenotype. In 3D alginate culture, NC activated NPC either in indirect co-culture or by addition of NCCM as indicated by the gene expression ratio of aggrecan/collagen type 2. This effect was strongest with 10% fetal calf serum and under hypoxia. Conversely, AFC seemed unresponsive to co-culture with pNC or to the NCCM. Further, the results showed that hypoxia led to decelerated metabolic activity, but did not lead to a significant change in the GAG/DNA ratio. Mass spectrometry identified connective tissue growth factor (CTGF, syn. CCN2) in the NCCM. Conclusions Our results confirm the requirement to culture NC in 3D to best maintain their phenotype, preferentially in hypoxia and with the supplementation of FCS in the culture media. Despite these advancements, the ideal culture condition remains to be identified. Electronic supplementary material The online version of this article (doi:10.1186/1471-2474-15-422) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Benjamin Gantenbein
- Tissue & Organ Mechanobiology, Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland.
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