1
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Sao K, Risbud MV. Sdc4 deletion perturbs intervertebral disc matrix homeostasis and promotes early osteopenia in the aging mouse spine. Matrix Biol 2024; 131:46-61. [PMID: 38806135 DOI: 10.1016/j.matbio.2024.05.006] [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: 01/10/2024] [Revised: 05/07/2024] [Accepted: 05/22/2024] [Indexed: 05/30/2024]
Abstract
Syndecan 4 (SDC4), a cell surface heparan sulfate proteoglycan, is known to regulate matrix catabolism by nucleus pulposus cells in an inflammatory milieu. However, the role of SDC4 in the aging spine has never been explored. Here we analyzed the spinal phenotype of Sdc4 global knockout (KO) mice as a function of age. Micro-computed tomography showed that Sdc4 deletion severely reduced vertebral trabecular and cortical bone mass, and biomechanical properties of vertebrae were significantly altered in Sdc4 KO mice. These changes in vertebral bone were likely due to elevated osteoclastic activity. The histological assessment showed subtle phenotypic changes in the intervertebral disc. Imaging-Fourier transform-infrared analyses showed a reduced relative ratio of mature collagen crosslinks in young adult nucleus pulposus (NP) and annulus fibrosus (AF) of KO compared to wildtype discs. Additionally, relative chondroitin sulfate levels increased in the NP compartment of the KO mice. Transcriptomic analysis of NP tissue using CompBio, an AI-based tool showed biological themes associated with prominent dysregulation of heparan sulfate GAG degradation, mitochondria metabolism, autophagy, endoplasmic reticulum (ER)-associated misfolded protein processes and ER to Golgi protein processing. Overall, this study highlights the important role of SDC4 in fine-tuning vertebral bone homeostasis and extracellular matrix homeostasis in the mouse intervertebral disc.
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Affiliation(s)
- Kimheak Sao
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, United States; Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut Street, Suite 501 College Bldg., Philadelphia, PA 19107, United States
| | - Makarand V Risbud
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, United States; Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut Street, Suite 501 College Bldg., Philadelphia, PA 19107, United States.
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2
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Couasnay G, Garcia H, Elefteriou F. A comparative analysis of TonEBP conditional knockout mouse models reveals inter-dependency between compartments of the intervertebral disc. Development 2024; 151:dev202354. [PMID: 38421307 PMCID: PMC11006390 DOI: 10.1242/dev.202354] [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: 09/13/2023] [Accepted: 02/20/2024] [Indexed: 03/02/2024]
Abstract
Interactions between notochord and sclerotome are required for normal embryonic spine patterning, but whether the postnatal derivatives of these tissues also require interactions for postnatal intervertebral disc (IVD) growth and maintenance is less established. We report here the comparative analysis of four conditional knockout mice deficient for TonEBP, a transcription factor known to allow cells to adapt to changes in extracellular osmotic pressure, in specific compartments of the IVD. We show that TonEBP deletion in nucleus pulposus (NP) cells does not affect their survival or aggrecan expression, but promoted cell proliferation in the NP and in adjacent vertebral growth plates (GPs). In cartilage end plates/GPs, TonEBP deletion induced cell death, but also structural alterations in the adjacent NP cells and vertebral bodies. Embryonic or postnatal TonEBP loss generated similar IVD changes. In addition to demonstrating the requirement of TonEBP in the different compartments of the IVD, this comparative analysis uncovers the in vivo interdependency of the different IVD compartments during the growth of the postnatal IVD-vertebral units.
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Affiliation(s)
- Greig Couasnay
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX 77030, USA
| | - Haley Garcia
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX 77030, USA
| | - Florent Elefteriou
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
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3
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Johnston SN, Tsingas M, Ain R, Barve RA, Risbud MV. Increased HIF-2α activity in the nucleus pulposus causes intervertebral disc degeneration in the aging mouse spine. Front Cell Dev Biol 2024; 12:1360376. [PMID: 38510179 PMCID: PMC10950937 DOI: 10.3389/fcell.2024.1360376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 02/21/2024] [Indexed: 03/22/2024] Open
Abstract
Hypoxia-inducible factors (HIFs) are essential to the homeostasis of hypoxic tissues. Although HIF-2α, is expressed in nucleus pulposus (NP) cells, consequences of elevated HIF-2 activity on disc health remains unknown. We expressed HIF-2α with proline to alanine substitutions (P405A; P531A) in the Oxygen-dependent degradation domain (HIF-2αdPA) in the NP tissue using an inducible, nucleus pulposus-specific K19CreERT allele to study HIF-2α function in the adult intervertebral disc. Expression of HIF-2α in NP impacted disc morphology, as evident from small but significantly higher scores of degeneration in NP of 24-month-old K19CreERT; HIF-2αdPA (K19-dPA) mice. Noteworthy, comparisons of grades within each genotype between 14 months and 24 months indicated that HIF-2α overexpression contributed to more pronounced changes than aging alone. The annulus fibrosus (AF) compartment in the 14-month-old K19-dPA mice exhibited lower collagen turnover and Fourier transform-infrared (FTIR) spectroscopic imaging analyses showed changes in the biochemical composition of the 14- and 24-month-old K19-dPA mice. Moreover, there were changes in aggrecan, chondroitin sulfate, and COMP abundance without alterations in NP phenotypic marker CA3, suggesting the overexpression of HIF-2α had some impact on matrix composition but not the cell phenotype. Mechanistically, the global transcriptomic analysis showed enrichment of differentially expressed genes in themes closely related to NP cell function such as cilia, SLIT/ROBO pathway, and HIF/Hypoxia signaling at both 14- and 24-month. Together, these findings underscore the role of HIF-2α in the pathogenesis of disc degeneration in the aged spine.
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Affiliation(s)
- Shira N. Johnston
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
| | - Maria Tsingas
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
| | - Rahatul Ain
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Pharmacology, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
| | - Ruteja A. Barve
- Department of Genetics, Genome Technology Access Centre at the McDonnell Genome Institute, Washington University, School of Medicine, St. Louis, MO, United States
| | - Makarand V. Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
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4
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Zhang L, Hu S, Xiu C, Li M, Zheng Y, Zhang R, Li B, Chen J. Intervertebral disc-intrinsic Hedgehog signaling maintains disc cell phenotypes and prevents disc degeneration through both cell autonomous and non-autonomous mechanisms. Cell Mol Life Sci 2024; 81:74. [PMID: 38308696 PMCID: PMC10838248 DOI: 10.1007/s00018-023-05106-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/18/2023] [Accepted: 12/22/2023] [Indexed: 02/05/2024]
Abstract
Intervertebral disc degeneration is closely related to abnormal phenotypic changes in disc cells. However, the mechanism by which disc cell phenotypes are maintained remains poorly understood. Here, Hedgehog-responsive cells were found to be specifically localized in the inner annulus fibrosus and cartilaginous endplate of postnatal discs, likely activated by Indian Hedgehog. Global inhibition of Hedgehog signaling using a pharmacological inhibitor or Agc1-CreERT2-mediated deletion of Smo in disc cells of juvenile mice led to spontaneous degenerative changes in annulus fibrosus and cartilaginous endplate accompanied by aberrant disc cell differentiation in adult mice. In contrast, Krt19-CreER-mediated deletion of Smo specifically in nucleus pulposus cells led to healthy discs and normal disc cell phenotypes. Similarly, age-related degeneration of nucleus pulposus was accelerated by genetic inactivation of Hedgehog signaling in all disc cells, but not in nucleus pulposus cells. Furthermore, inactivation of Gli2 in disc cells resulted in partial loss of the vertebral growth plate but otherwise healthy discs, whereas deletion of Gli3 in disc cells largely corrected disc defects caused by Smo ablation in mice. Taken together, our findings not only revealed for the first time a direct role of Hedgehog-Gli3 signaling in maintaining homeostasis and cell phenotypes of annuls fibrosus and cartilaginous endplate, but also identified disc-intrinsic Hedgehog signaling as a novel non-cell-autonomous mechanism to regulate nucleus pulposus cell phenotype and protect mice from age-dependent nucleus pulposus degeneration. Thus, targeting Hedgehog signaling may represent a potential therapeutic strategy for the prevention and treatment of intervertebral disc degeneration.
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Affiliation(s)
- Lei Zhang
- Department of Clinical Medicine, Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China
| | - Siyuan Hu
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China
| | - Chunmei Xiu
- Department of Clinical Medicine, Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China
| | - Meng Li
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China
| | - Yixin Zheng
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China
| | - Rui Zhang
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China
| | - Bin Li
- Department of Clinical Medicine, Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China.
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China.
| | - Jianquan Chen
- Department of Clinical Medicine, Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China.
- Orthopedic Institute, Suzhou Medical College, Soochow University, Suzhou, 215006, Jiangsu, China.
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5
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Novais EJ, Narayanan R, Canseco JA, van de Wetering K, Kepler CK, Hilibrand AS, Vaccaro AR, Risbud MV. A new perspective on intervertebral disc calcification-from bench to bedside. Bone Res 2024; 12:3. [PMID: 38253615 PMCID: PMC10803356 DOI: 10.1038/s41413-023-00307-3] [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: 10/15/2023] [Revised: 12/04/2023] [Accepted: 12/05/2023] [Indexed: 01/24/2024] Open
Abstract
Disc degeneration primarily contributes to chronic low back and neck pain. Consequently, there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis, ectopic calcification, herniation, or mixed phenotypes. Amongst these phenotypes, disc calcification is the least studied. Ectopic calcification, by definition, is the pathological mineralization of soft tissues, widely studied in the context of conditions that afflict vasculature, skin, and cartilage. Clinically, disc calcification is associated with poor surgical outcomes and back pain refractory to conservative treatment. It is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular and morphological characteristics: hypertrophic chondrocyte-like cell differentiation; TNAP, ENPP1, and ANK upregulation; cell death; altered Pi and PPi homeostasis; and local inflammation. Recent studies in mouse models have provided a better understanding of the mechanisms underlying this phenotype. It is essential to recognize that the presentation and nature of mineralization differ between AF, NP, and EP compartments. Moreover, the combination of anatomic location, genetics, and environmental stressors, such as aging or trauma, govern the predisposition to calcification. Lastly, the systemic regulation of calcium and Pi metabolism is less important than the local activity of PPi modulated by the ANK-ENPP1 axis, along with disc cell death and differentiation status. While there is limited understanding of this phenotype, understanding the molecular pathways governing local intervertebral disc calcification may lead to developing disease-modifying drugs and better clinical management of degeneration-related pathologies.
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Affiliation(s)
- Emanuel J Novais
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
- Unidade Local de Saúde do Litoral Alentejano, Orthopedic Department, Santiago do Cacém, Portugal
| | - Rajkishen Narayanan
- Rothman Orthopedic Institute at Thomas Jefferson University, Philadelphia, PA, USA
| | - Jose A Canseco
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
- Rothman Orthopedic Institute at Thomas Jefferson University, Philadelphia, PA, USA
| | - Koen van de Wetering
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Christopher K Kepler
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
- Rothman Orthopedic Institute at Thomas Jefferson University, Philadelphia, PA, USA
| | - Alan S Hilibrand
- Rothman Orthopedic Institute at Thomas Jefferson University, Philadelphia, PA, USA
| | - Alexander R Vaccaro
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
- Rothman Orthopedic Institute at Thomas Jefferson University, Philadelphia, PA, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.
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6
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Wang X, Zeng Q, Ge Q, Hu S, Jin H, Wang PE, Li J. Protective effects of Shensuitongzhi formula on intervertebral disc degeneration via downregulation of NF-κB signaling pathway and inflammatory response. J Orthop Surg Res 2024; 19:80. [PMID: 38243334 PMCID: PMC10799454 DOI: 10.1186/s13018-023-04391-3] [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: 08/25/2023] [Accepted: 11/18/2023] [Indexed: 01/21/2024] Open
Abstract
Low back pain (LBP) is a common orthopedic disease over the world. Lumbar intervertebral disc degeneration (IDD) is regarded as an important cause of LBP. Shensuitongzhi formula (SSTZF) is a drug used in clinical treatment for orthopedic diseases. It has been found that SSTZF can have a good treatment for IDD. But the exact mechanism has not been clarified. The results showed that SSTZF protects against LSI-induced degeneration of cartilage endplates and intervertebral discs. Meanwhile, SSTZF treatment dramatically reduces the expression of inflammatory factor as well as the expression of catabolism protein and upregulates the expression of anabolism protein in LSI-induced mice. In addition, SSTZF delayed the progression of LSI-induced IDD via downregulation the level of NF-κB signaling key gene RELA and phosphorylation of key protein P65 in endplate chondrocytes. Our study has illustrated the treatment as well as the latent mechanism of SSTZF in IDD.
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Affiliation(s)
- Xu Wang
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
- The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Qinghe Zeng
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
- The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Qinwen Ge
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
- The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Songfeng Hu
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
- The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China
- Department of Orthopaedics and Traumatology, Shaoxing Hospital of Traditional Chinese Medicine, Shaoxing, 312000, Zhejiang, China
| | - Hongting Jin
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
| | - Ping-Er Wang
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China.
| | - Ju Li
- Institute of Orthopedics and Traumatology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China.
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310006, China.
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7
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Johnston SN, Tsingas M, Ain R, Barve RA, Risbud MV. Increased HIF-2α Activity in the Nucleus Pulposus Causes Intervertebral Disc Degeneration in the Aging Mouse Spine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573086. [PMID: 38187709 PMCID: PMC10769411 DOI: 10.1101/2023.12.22.573086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Hypoxia-inducible factors (HIFs) are essential to the homeostasis of hypoxic tissues. Although HIF-2α, is expressed in nucleus pulposus (NP) cells, consequences of elevated HIF-2 activity on disc health remains unknown. We expressed HIF-2α with proline to alanine substitutions (P405A;P531A) in the Oxygen-dependent degradation domain (HIF-2αdPA) in the NP tissue using an inducible, nucleus pulposus-specific K19 CreERT allele to study HIF-2α function in the adult intervertebral disc. Expression of HIF-2α in NP impacted disc morphology, as evident from small but significantly higher scores of degeneration in NP of 24-month-old K19 CreERT ; HIF-2α dPA (K19-dPA) mice. Noteworthy, comparisons of grades within each genotype between 14 months and 24 months indicated that HIF-2α overexpression contributed to more pronounced changes than aging alone. The annulus fibrosus (AF) compartment in the 14-month-old K19-dPA mice exhibited lower collagen turnover and Fourier transform-infrared (FTIR) spectroscopic imaging analyses showed changes in the biochemical composition of the 14-and 24-month-old K19-dPA mice. Moreover, there were changes in aggrecan, chondroitin sulfate, and COMP abundance without alterations in NP phenotypic marker CA3, suggesting the overexpression of HIF-2α had some impact on matrix composition but not the cell phenotype. Mechanistically, the global transcriptomic analysis showed enrichment of differentially expressed genes in themes closely related to NP cell function such as cilia, SLIT/ROBO pathway, and HIF/Hypoxia signaling at both 14- and 24-months. Together, these findings underscore the role of HIF-2α in the pathogenesis of disc degeneration in the aged spine.
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8
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Lei M, Lin H, Shi D, Hong P, Song H, Herman B, Liao Z, Yang C. Molecular mechanism and therapeutic potential of HDAC9 in intervertebral disc degeneration. Cell Mol Biol Lett 2023; 28:104. [PMID: 38093179 PMCID: PMC10717711 DOI: 10.1186/s11658-023-00517-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Intervertebral disc degeneration (IVDD) is the major cause of low-back pain. Histone deacetylase 9 (HDAC9) was dramatically decreased in the degenerative nucleus pulposus (NP) samples of patients with intervertebral disc degeneration (IVDD) according to bioinformatics analysis of Gene Expression Omnibus (GEO) GSE56081 dataset. This study aims to investigate the role of HDAC9 in IVDD progression. METHODS The contribution of HDAC9 to the progression of IVDD was assessed using HDAC9 knockout (HDAC9KO) mice and NP-targeted HDAC9-overexpressing mice by IVD injection of adenovirus-mediated HDAC9 under a Col2a1 promoter. Magnetic resonance imaging (MRI) and histological analysis were used to examine the degeneration of IVD. NP cells were isolated from mice to investigate the effects of HDAC9 on apoptosis and viability. mRNA-seq and coimmunoprecipitation/mass spectrometry (co-IP/MS) analysis were used to analyze the HDAC9-regulated factors in the primary cultured NP cells. RESULTS HDAC9 was statistically decreased in the NP tissues in aged mice. HDAC9KO mice spontaneously developed age-related IVDD compared with wild-type (HDAC9WT) mice. In addition, overexpression of HDAC9 in NP cells alleviated IVDD symptoms in a surgically-induced IVDD mouse model. In an in vitro assay, knockdown of HDAC9 inhibited cell viability and promoted cell apoptosis of NP cells, and HDAC9 overexpression had the opposite effects in NP cells isolated from HDAC9KO mice. Results of mRNA-seq and co-IP/MS analysis revealed the possible proteins and signaling pathways regulated by HDAC9 in NP cells. RUNX family transcription factor 3 (RUNX3) was screened out for further study, and RUNX3 was found to be deacetylated and stabilized by HDAC9. Knockdown of RUNX3 restored the effects of HDAC9 silencing on NP cells by inhibiting apoptosis and increasing viability. CONCLUSION Our results suggest that HDAC9 plays an important role in the development and progression of IVDD. It might be required to protect NP cells against the loss of cell viability and apoptosis by inhibiting RUNX3 acetylation and expression during IVDD. Together, our findings suggest that HDAC9 may be a potential therapeutic target in IVDD.
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Affiliation(s)
- Ming Lei
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
| | - Hui Lin
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Deyao Shi
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Pan Hong
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Hui Song
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Bomansaan Herman
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Zhiwei Liao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
| | - Cao Yang
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
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9
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Luo Z, Wei Z, Zhang G, Chen H, Li L, Kang X. Achilles' Heel-The Significance of Maintaining Microenvironmental Homeostasis in the Nucleus Pulposus for Intervertebral Discs. Int J Mol Sci 2023; 24:16592. [PMID: 38068915 PMCID: PMC10706299 DOI: 10.3390/ijms242316592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/02/2023] [Accepted: 11/07/2023] [Indexed: 12/18/2023] Open
Abstract
The dysregulation of intracellular and extracellular environments as well as the aberrant expression of ion channels on the cell membrane are intricately linked to a diverse array of degenerative disorders, including intervertebral disc degeneration. This condition is a significant contributor to low back pain, which poses a substantial burden on both personal quality of life and societal economics. Changes in the number and function of ion channels can disrupt the water and ion balance both inside and outside cells, thereby impacting the physiological functions of tissues and organs. Therefore, maintaining ion homeostasis and stable expression of ion channels within the cellular microenvironment may prove beneficial in the treatment of disc degeneration. Aquaporin (AQP), calcium ion channels, and acid-sensitive ion channels (ASIC) play crucial roles in regulating water, calcium ions, and hydrogen ions levels. These channels have significant effects on physiological and pathological processes such as cellular aging, inflammatory response, stromal decomposition, endoplasmic reticulum stress, and accumulation of cell metabolites. Additionally, Piezo 1, transient receptor potential vanilloid type 4 (TRPV4), tension response enhancer binding protein (TonEBP), potassium ions, zinc ions, and tungsten all play a role in the process of intervertebral disc degeneration. This review endeavors to elucidate alterations in the microenvironment of the nucleus pulposus during intervertebral disc degeneration (IVDD), with a view to offer novel insights and approaches for exploring therapeutic interventions against disc degeneration.
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Affiliation(s)
- Zhangbin Luo
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
- The Second Clinical Medical College, Lanzhou University, Lanzhou 730030, China
| | - Ziyan Wei
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
- The Second Clinical Medical College, Lanzhou University, Lanzhou 730030, China
| | - Guangzhi Zhang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
- The Second Clinical Medical College, Lanzhou University, Lanzhou 730030, China
| | - Haiwei Chen
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
| | - Lei Li
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
- The Second Clinical Medical College, Lanzhou University, Lanzhou 730030, China
| | - Xuewen Kang
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China; (Z.L.); (Z.W.); (G.Z.); (H.C.); (L.L.)
- The Second Clinical Medical College, Lanzhou University, Lanzhou 730030, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou University Second Hospital, Lanzhou 730030, China
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10
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Zhang GZ, Li L, Luo ZB, Zhang CY, Wang YG, Kang XW. Identification and experimental validation of key extracellular proteins as potential targets in intervertebral disc degeneration. Bone Joint Res 2023; 12:522-535. [PMID: 37661086 PMCID: PMC10475329 DOI: 10.1302/2046-3758.129.bjr-2022-0369.r2] [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] [Indexed: 09/05/2023] Open
Abstract
Aims This study aimed, through bioinformatics analysis and in vitro experiment validation, to identify the key extracellular proteins of intervertebral disc degeneration (IDD). Methods The gene expression profile of GSE23130 was downloaded from the Gene Expression Omnibus (GEO) database. Extracellular protein-differentially expressed genes (EP-DEGs) were screened by protein annotation databases, and we used Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) to analyze the functions and pathways of EP-DEGs. STRING and Cytoscape were used to construct protein-protein interaction (PPI) networks and identify hub EP-DEGs. NetworkAnalyst was used to analyze transcription factors (TFs) and microRNAs (miRNAs) that regulate hub EP-DEGs. A search of the Drug Signatures Database (DSigDB) for hub EP-DEGs revealed multiple drug molecules and drug-target interactions. Results A total of 56 EP-DEGs were identified in the differential expression analysis. EP-DEGs were enriched in the extracellular structure organization, ageing, collagen-activated signalling pathway, PI3K-Akt signalling pathway, and AGE-RAGE signalling pathway. PPI network analysis showed that the top ten hub EP-DEGs are closely related to IDD. Correlation analysis also demonstrated a significant correlation between the ten hub EP-DEGs (p<0.05), which were selected to construct TF-gene interaction and TF-miRNA coregulatory networks. In addition, ten candidate drugs were screened for the treatment of IDD. Conclusion The findings clarify the roles of extracellular proteins in IDD and highlight their potential as promising novel therapeutic targets.
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Affiliation(s)
- Guang-Zhi Zhang
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
| | - Lei Li
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
| | - Zhang-Bin Luo
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
| | - Cang-Yu Zhang
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
| | - Yong-Gang Wang
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
| | - Xue-Wen Kang
- Department of Orthopaedics, Lanzhou University Second Hospital, Lanzhou, China
- The Second Clinical Medical College, Lanzhou University, Lanzhou, China
- Key Laboratory of Orthopedics Disease of Gansu Province, Lanzhou, China
- The International Cooperation Base of Gansu Province for The Pain Research in Spinal Disorders, Lanzhou, China
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11
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Ohnishi T, Tran V, Sao K, Ramteke P, Querido W, Barve RA, van de Wetering K, Risbud MV. Loss of function mutation in Ank causes aberrant mineralization and acquisition of osteoblast-like-phenotype by the cells of the intervertebral disc. Cell Death Dis 2023; 14:447. [PMID: 37468461 PMCID: PMC10356955 DOI: 10.1038/s41419-023-05893-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 06/09/2023] [Accepted: 06/15/2023] [Indexed: 07/21/2023]
Abstract
Pathological mineralization of intervertebral disc is debilitating and painful and linked to disc degeneration in a subset of human patients. An adenosine triphosphate efflux transporter, progressive ankylosis (ANK) is a regulator of extracellular inorganic pyrophosphate levels and plays an important role in tissue mineralization. However, the function of ANK in intervertebral disc has not been fully explored. Herein we analyzed the spinal phenotype of Ank mutant mice (ank/ank) with attenuated ANK function. Micro-computed tomography and histological analysis showed that loss of ANK function results in the aberrant annulus fibrosus mineralization and peripheral disc fusions with cranial to caudal progression in the spine. Vertebrae in ank mice exhibit elevated cortical bone mass and increased tissue non-specific alkaline phosphatase-positive endplate chondrocytes with decreased subchondral endplate porosity. The acellular dystrophic mineral inclusions in the annulus fibrosus were localized adjacent to apoptotic cells and cells that acquired osteoblast-like phenotype. Fourier transform infrared spectral imaging showed that the apatite mineral in the outer annulus fibrosus had similar chemical composition to that of vertebral bone. Transcriptomic analysis of annulus fibrosus and nucleus pulposus tissues showed changes in several biological themes with a prominent dysregulation of BMAL1/CLOCK circadian regulation. The present study provides new insights into the role of ANK in the disc tissue compartments and highlights the importance of local inorganic pyrophosphate metabolism in inhibiting the mineralization of this important connective tissue.
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Affiliation(s)
- Takashi Ohnishi
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
- Department of Orthopaedic Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, 060-8638, Japan
| | - Victoria Tran
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Kimheak Sao
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Pranay Ramteke
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - William Querido
- Department of Bioengineering, Temple University, Philadelphia, PA, 19122, USA
| | - Ruteja A Barve
- Department of Genetics, Genome Technology Access Centre at the McDonnell Genome Institute, Washington University, School of Medicine, St. Louis, MO, 63110, USA
| | - Koen van de Wetering
- Department of Dermatology and Cutaneous Biology, Jefferson Institute of Molecular Medicine and PXE International Center of Excellence in Research and Clinical Care, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
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12
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Madhu V, Hernandez-Meadows M, Boneski PK, Qiu Y, Guntur AR, Kurland IJ, Barve RA, Risbud MV. The mitophagy receptor BNIP3 is critical for the regulation of metabolic homeostasis and mitochondrial function in the nucleus pulposus cells of the intervertebral disc. Autophagy 2023; 19:1821-1843. [PMID: 36628478 PMCID: PMC10262801 DOI: 10.1080/15548627.2022.2162245] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/13/2022] [Accepted: 12/20/2022] [Indexed: 01/12/2023] Open
Abstract
The contribution of mitochondria to the metabolic function of hypoxic NP cells has been overlooked. We have shown that NP cells contain networked mitochondria and that mitochondrial translocation of BNIP3 mediates hypoxia-induced mitophagy. However, whether BNIP3 also plays a role in governing mitochondrial function and metabolism in hypoxic NP cells is not known. BNIP3 knockdown altered mitochondrial morphology, and number, and increased mitophagy. Interestingly, BNIP3 deficiency in NP cells reduced glycolytic capacity reflected by lower production of lactate/H+ and lower ATP production rate. Widely targeted metabolic profiling and flux analysis using 1-2-13C-glucose showed that the BNIP3 loss resulted in redirection of glycolytic flux into pentose phosphate and hexosamine biosynthesis as well as pyruvate resulting in increased TCA flux. An overall reduction in one-carbon metabolism was noted suggesting reduced biosynthesis. U13C-glutamine flux analysis showed preservation of glutamine utilization to maintain TCA intermediates. The transcriptomic analysis of the BNIP3-deficient cells showed dysregulation of cellular functions including membrane and cytoskeletal integrity, ECM-growth factor signaling, and protein quality control with an overall increase in themes related to angiogenesis and innate immune response. Importantly, we observed strong thematic similarities with the transcriptome of a subset of human degenerative samples. Last, we noted increased autophagic flux, decreased disc height index and aberrant COL10A1/collagen X expression, signs of early disc degeneration in young adult bnip3 knockout mice. These results suggested that in addition to mitophagy regulation, BNIP3 plays a role in maintaining mitochondrial function and metabolism, and dysregulation of mitochondrial homeostasis could promote disc degeneration.Abbreviations: ECAR extracellular acidification rate; HIF hypoxia inducible factor; MFA metabolic flux analysis; NP nucleus pulposus; OCR oxygen consumption rate; ShBnip3 short-hairpin Bnip3.
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Affiliation(s)
- Vedavathi Madhu
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Miriam Hernandez-Meadows
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Paige K Boneski
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Yunping Qiu
- Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, Bronx, NY, USA
| | - Anyonya R Guntur
- Center for Molecular Medicine, Maine Medical Center Research Institute, Scarborough, ME, USA
| | - Irwin J. Kurland
- Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ruteja A Barve
- Department of Genetics, Genome Technology Access Centre at the McDonnell Genome Institute, Washington University, School of Medicine, St. Louis, MO, USA
| | - Makarand V. Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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13
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Johnston SN, Silagi ES, Madhu V, Nguyen DH, Shapiro IM, Risbud MV. GLUT1 is redundant in hypoxic and glycolytic nucleus pulposus cells of the intervertebral disc. JCI Insight 2023; 8:e164883. [PMID: 36917198 PMCID: PMC10243741 DOI: 10.1172/jci.insight.164883] [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] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 03/08/2023] [Indexed: 03/15/2023] Open
Abstract
Glycolysis is central to homeostasis of nucleus pulposus (NP) cells in the avascular intervertebral disc. Since the glucose transporter, GLUT1, is a highly enriched phenotypic marker of NP cells, we hypothesized that it is vital for the development and postnatal maintenance of the disc. Surprisingly, primary NP cells treated with 2 well-characterized GLUT1 inhibitors maintained normal rates of glycolysis and ATP production, indicating intrinsic compensatory mechanisms. We showed in vitro that NP cells mitigated GLUT1 loss by rewiring glucose import through GLUT3. Of note, we demonstrated that substrates, such as glutamine and palmitate, did not compensate for glucose restriction resulting from dual inhibition of GLUT1/3, and inhibition compromised long-term cell viability. To investigate the redundancy of GLUT1 function in NP, we generated 2 NP-specific knockout mice: Krt19CreERT Glut1fl/fl and Foxa2Cre Glut1fl/fl. There were no apparent defects in postnatal disc health or development and maturation in mutant mice. Microarray analysis verified that GLUT1 loss did not cause transcriptomic alterations in the NP, supporting that cells are refractory to GLUT1 loss. These observations provide the first evidence to our knowledge of functional redundancy in GLUT transporters in the physiologically hypoxic intervertebral disc and underscore the importance of glucose as the indispensable substrate for NP cells.
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Affiliation(s)
- Shira N. Johnston
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
- Graduate Program in Cell Biology and Regenerative Medicine, College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Elizabeth S. Silagi
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
- Graduate Program in Cell Biology and Regenerative Medicine, College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Vedavathi Madhu
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
| | - Duc H. Nguyen
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
- Graduate Program in Cell Biology and Regenerative Medicine, College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Irving M. Shapiro
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
- Graduate Program in Cell Biology and Regenerative Medicine, College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Makarand V. Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, and
- Graduate Program in Cell Biology and Regenerative Medicine, College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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14
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Liang T, Gao B, Zhou J, Qiu X, Qiu J, Chen T, Liang Y, Gao W, Qiu X, Lin Y. Constructing intervertebral disc degeneration animal model: A review of current models. Front Surg 2023; 9:1089244. [PMID: 36969323 PMCID: PMC10036602 DOI: 10.3389/fsurg.2022.1089244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 12/08/2022] [Indexed: 03/12/2023] Open
Abstract
Low back pain is one of the top disorders that leads to disability and affects disability-adjusted life years (DALY) globally. Intervertebral disc degeneration (IDD) and subsequent discogenic pain composed major causes of low back pain. Recent studies have identified several important risk factors contributing to IDD's development, such as inflammation, mechanical imbalance, and aging. Based on these etiology findings, three categories of animal models for inducing IDD are developed: the damage-induced model, the mechanical model, and the spontaneous model. These models are essential measures in studying the natural history of IDD and finding the possible therapeutic target against IDD. In this review, we will discuss the technical details of these models, the duration between model establishment, the occurrence of observable degeneration, and the potential in different study ranges. In promoting future research for IDD, each animal model should examine its concordance with natural IDD pathogenesis in humans. We hope this review can enhance the understanding and proper use of multiple animal models, which may attract more attention to this disease and contribute to translation research.
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Affiliation(s)
- Tongzhou Liang
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Bo Gao
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Jinlang Zhou
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xianjian Qiu
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Jincheng Qiu
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Taiqiu Chen
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Yanfang Liang
- Department of Operating Theater, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Wenjie Gao
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xuemei Qiu
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
- Correspondence: Xuemei Qiu Youxi Lin
| | - Youxi Lin
- Department of Orthopedic Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China
- Correspondence: Xuemei Qiu Youxi Lin
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15
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Lu Z, Chen P, Xu Q, Li B, Jiang S, Jiang L, Zheng X. Constitutive and conditional gene knockout mice for the study of intervertebral disc degeneration: Current status, decision considerations, and future possibilities. JOR Spine 2023; 6:e1242. [PMID: 36994464 PMCID: PMC10041386 DOI: 10.1002/jsp2.1242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 12/13/2022] [Accepted: 12/22/2022] [Indexed: 01/09/2023] Open
Abstract
There have been an increasing number of patients with degenerative disc diseases due to the aging population. In light of this, studies on the pathogenesis of intervertebral disc degeneration have become a hot topic, and gene knockout mice have become a valuable tool in this field of research. With the development of science and technology, constitutive gene knockout mice can be constructed using homologous recombination, zinc finger nuclease, transcription activator-like effector nuclease technology and clustered regularly interspaced short palindromic repeats/Cas9 (CRISPR/Cas9) system, and conditional gene knockout mice can be constructed using the Cre/LoxP system. The gene-edited mice using these techniques have been widely used in the studies on disc degeneration. This paper reviews the development process and principles of these technologies, functions of the edited genes in disc degeneration, advantages, and disadvantages of different methods and possible targets of the specific Cre recombinase in intervertebral discs. Recommendations for the choice of suitable gene-edited model mice are presented. At the same time, possible technological improvements in the future are also discussed.
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Affiliation(s)
- Ze‐Yu Lu
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Peng‐Bo Chen
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Qing‐Yin Xu
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Bo Li
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Sheng‐Dan Jiang
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Lei‐Sheng Jiang
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Xin‐Feng Zheng
- Spine Center Xinhua Hospital, Shanghai Jiao Tong University School of Medicine Shanghai China
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16
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Poletto DL, Crowley JD, Tanglay O, Walsh WR, Pelletier MH. Preclinical in vivo animal models of intervertebral disc degeneration. Part 1: A systematic review. JOR Spine 2022; 6:e1234. [PMID: 36994459 PMCID: PMC10041387 DOI: 10.1002/jsp2.1234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 10/10/2022] [Accepted: 10/23/2022] [Indexed: 12/24/2022] Open
Abstract
Intervertebral disc degeneration (IVDD), a widely recognized cause of lower back pain, is the leading cause of disability worldwide. A myriad of preclinical in vivo animal models of IVDD have been described in the literature. There is a need for critical evaluation of these models to better inform researchers and clinicians to optimize study design and ultimately, enhance experimental outcomes. The purpose of this study was to conduct an extensive systematic literature review to report the variability of animal species, IVDD induction method, and experimental timepoints and endpoints used in in vivo IVDD preclinical research. A systematic literature review of peer-reviewed manuscripts featured on PubMed and EMBASE databases was conducted in accordance with PRISMA guidelines. Studies were included if they reported an in vivo animal model of IVDD and included details of the species used, how disc degeneration was induced, and the experimental endpoints used for analysis. Two-hundred and fifty-nine (259) studies were reviewed. The most common species, IVDD induction method and experimental endpoint used was rodents(140/259, 54.05%), surgery (168/259, 64.86%) and histology (217/259, 83.78%), respectively. Experimental timepoint varied greatly between studies, ranging from 1 week (dog and rodent models), to >104 weeks in dog, horse, monkey, rabbit, and sheep models. The two most common timepoints used across all species were 4 weeks (49 manuscripts) and 12 weeks (44 manuscripts). A comprehensive discussion of the species, methods of IVDD induction and experimental endpoints is presented. There was great variability across all categories: animal species, method of IVDD induction, timepoints and experimental endpoints. While no animal model can replicate the human scenario, the most appropriate model should be selected in line with the study objectives to optimize experimental design, outcomes and improve comparisons between studies.
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Affiliation(s)
- Daniel L. Poletto
- Surgical and Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, Faculty of Medicine University of New South Wales (UNSW) Sydney, Prince of Wales Hospital Sydney Australia
| | - James D. Crowley
- Surgical and Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, Faculty of Medicine University of New South Wales (UNSW) Sydney, Prince of Wales Hospital Sydney Australia
| | - Onur Tanglay
- Surgical and Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, Faculty of Medicine University of New South Wales (UNSW) Sydney, Prince of Wales Hospital Sydney Australia
| | - William R. Walsh
- Surgical and Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, Faculty of Medicine University of New South Wales (UNSW) Sydney, Prince of Wales Hospital Sydney Australia
| | - Matthew H. Pelletier
- Surgical and Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, Faculty of Medicine University of New South Wales (UNSW) Sydney, Prince of Wales Hospital Sydney Australia
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17
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Johnston SN, Madhu V, Shapiro IM, Risbud MV. Conditional Deletion of HIF-2α in Mouse Nucleus Pulposus Reduces Fibrosis and Provides Mild and Transient Protection From Age-Dependent Structural Changes in Intervertebral Disc. J Bone Miner Res 2022; 37:2512-2530. [PMID: 36117450 PMCID: PMC9772060 DOI: 10.1002/jbmr.4707] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/05/2022] [Accepted: 07/29/2022] [Indexed: 01/19/2023]
Abstract
Hypoxia-inducible factors (HIFs) are critical to the development and homeostasis of hypoxic tissues. Although HIF-2α, one of the main HIF-α isoforms, is expressed in nucleus pulposus (NP) cells, its functions remain unknown. We deleted HIF-2α in the NP tissue using a notochord-specific FoxA2Cre allele to study HIF-2α function in the adult intervertebral disc. Unlike observations in HIF-1αcKO mice, fate mapping studies using Rosa26-mTmG reporter showed that HIF-2α loss in NP did not negatively impact cell survival or affect compartment development. Rather, loss of HIF-2α resulted in slightly better attributes of NP morphology in 14-month-old HIF-2αcKO mice as evident from lower scores of degeneration. These 14-month-old HIF-2αcKO mice also exhibited significant reduction in NP tissue fibrosis and lower collagen turnover in the annulus fibrosis (AF) compartment. Imaging-Fourier transform-infrared (FTIR) analyses showed decreased collagen and protein content in the NP and maintained chondroitin sulfate levels in 14-month-old HIF-2αcKO . Mechanistically, global transcriptomic analysis showed enrichment of differentially expressed genes with Gene Ontology (GO) terms related to metabolic processes and cell development, molecular functions concerned with histone and protein binding, and associated pathways, including oxidative stress. Noteworthy, these morphological differences were not apparent in 24-month-old HIF-2αcKO , indicating that aging is the dominant factor in governing disc health. Together these data suggest that loss of HIF-2α in the NP compartment is not detrimental to the intervertebral disc development but rather mitigates NP tissue fibrosis and offers mild but transient protection from age-dependent early degenerative changes. © 2022 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Shira N. Johnston
- Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Vedavathi Madhu
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Irving M. Shapiro
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Makarand V. Risbud
- Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
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miR-31 from Mesenchymal Stem Cell-Derived Extracellular Vesicles Alleviates Intervertebral Disc Degeneration by Inhibiting NFAT5 and Upregulating the Wnt/β-Catenin Pathway. Stem Cells Int 2022; 2022:2164057. [PMID: 36311041 PMCID: PMC9615555 DOI: 10.1155/2022/2164057] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 04/26/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
In this study, we explored the regulatory mechanism of intervertebral disc degeneration (IDD) that involves miR-31 shuttled by bone marrow mesenchymal stem cell-derived extracellular vesicles (BMSC-EVs) and its downstream signaling molecules. Nucleus pulposus cells (NPCs) were isolated and treated with TNF-α to simulate IDD in vitro. The TNF-α-exposed NPCs were then cocultured with hBMSCs or hBMSC-EVs in vitro to detect the effects of hBMSC-EVs on NPC viability, apoptosis, and ECM degradation. Binding between miR-31 and NFAT5 was determined. A mouse model of IDD was prepared by vertebral disc puncture and injected with EVs from hBMSCs with miR-31 knockdown to discern the function of miR-31 in vivo. The results demonstrated that hBMSC-EVs delivered miR-31 into NPCs. hBMSC-EVs enhanced NPC proliferation and suppressed cell apoptosis and ECM degradation, which was associated with the transfer of miR-31 into NPCs. In NPCs, miR-31 bound to the 3′UTR of NFAT5 and inhibited NFAT5 expression, leading to activation of the Wnt/β-catenin pathway and thus promoting NPC proliferation and reducing cell apoptosis and ECM degradation. In addition, miR-31 in hBMSC-EVs alleviated the IDD in mouse models. Taken together, miR-31 in hBMSC-EVs can alleviate IDD by targeting NFAT5 and activating the Wnt/β-catenin pathway.
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Current Perspectives on Nucleus Pulposus Fibrosis in Disc Degeneration and Repair. Int J Mol Sci 2022; 23:ijms23126612. [PMID: 35743056 PMCID: PMC9223673 DOI: 10.3390/ijms23126612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/10/2022] [Accepted: 06/11/2022] [Indexed: 11/17/2022] Open
Abstract
A growing body of evidence in humans and animal models indicates an association between intervertebral disc degeneration (IDD) and increased fibrotic elements in the nucleus pulposus (NP). These include enhanced matrix turnover along with the abnormal deposition of collagens and other fibrous matrices, the emergence of fibrosis effector cells, such as macrophages and active fibroblasts, and the upregulation of the fibroinflammatory factors TGF-β1 and IL-1/-13. Studies have suggested a role for NP cells in fibroblastic differentiation through the TGF-βR1-Smad2/3 pathway, inflammatory activation and mechanosensing machineries. Moreover, NP fibrosis is linked to abnormal MMP activity, consistent with the role of matrix proteases in regulating tissue fibrosis. MMP-2 and MMP-12 are the two main profibrogenic markers of myofibroblastic NP cells. This review revisits studies in the literature relevant to NP fibrosis in an attempt to stratify its biochemical features and the molecular identity of fibroblastic cells in the context of IDD. Given the role of fibrosis in tissue healing and diseases, the perspective may provide new insights into the pathomechanism of IDD and its management.
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Ottone OK, Kim C, Collins JA, Risbud MV. The cGAS-STING Pathway Affects Vertebral Bone but Does Not Promote Intervertebral Disc Cell Senescence or Degeneration. Front Immunol 2022; 13:882407. [PMID: 35769461 PMCID: PMC9235924 DOI: 10.3389/fimmu.2022.882407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/06/2022] [Indexed: 11/25/2022] Open
Abstract
The DNA-sensing cGAS-STING pathway promotes the senescence-associated secretory phenotype (SASP) and mediates type-I interferon inflammatory responses to foreign viral and bacterial DNA as well as self-DNA. Studies of the intervertebral disc in humans and mice demonstrate associations between aging, increased cell senescence, and disc degeneration. Herein we assessed the role of STING in SASP promotion in STING gain- (N153S) and loss-of-function mouse models. N153S mice evidenced elevated circulating levels of proinflammatory markers including IL-1β, IL-6, and TNF-α, showed elevated monocyte and macrophage abundance in the vertebral marrow, and exhibited a mild trabecular and cortical bone phenotype in caudal vertebrae. Interestingly, despite systemic inflammation, the structural integrity of the disc and knee articular joint remained intact, and cells did not show a loss of their phenotype or elevated SASP. Transcriptomic analysis of N153S tissues demonstrated an upregulated immune response by disc cells, which did not closely resemble inflammatory changes in human tissues. Interestingly, STING-/- mice also showed a mild vertebral bone phenotype, but the absence of STING did not reduce the abundance of SASP markers or improve the age-associated disc phenotype. Overall, the analyses of N153S and STING-/- mice suggest that the cGAS-STING pathway is not a major contributor to SASP induction and consequent disc aging and degeneration but may play a minor role in the maintenance of trabecular bone in the vertebrae. This work contributes to a growing body of work demonstrating that systemic inflammation is not a key driver of disc degeneration.
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Affiliation(s)
- Olivia K. Ottone
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
| | - Cheeho Kim
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - John A. Collins
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Makarand V. Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
- Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA, United States
- *Correspondence: Makarand V. Risbud,
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21
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Boneski PK, Madhu V, Tomlinson RE, Shapiro IM, van de Wetering K, Risbud MV. Abcc6 Null Mice—a Model for Mineralization Disorder PXE Shows Vertebral Osteopenia Without Enhanced Intervertebral Disc Calcification With Aging. Front Cell Dev Biol 2022; 10:823249. [PMID: 35186933 PMCID: PMC8850990 DOI: 10.3389/fcell.2022.823249] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 01/03/2022] [Indexed: 12/12/2022] Open
Abstract
Chronic low back pain is a highly prevalent health condition intricately linked to intervertebral disc degeneration. One of the prominent features of disc degeneration that is commonly observed with aging is dystrophic calcification. ATP-binding cassette sub-family C member 6 (ABCC6), a presumed ATP efflux transporter, is a key regulator of systemic levels of the mineralization inhibitor pyrophosphate (PPi). Mutations in ABCC6 result in pseudoxanthoma elasticum (PXE), a progressive human metabolic disorder characterized by mineralization of the skin and elastic tissues. The implications of ABCC6 loss-of-function on pathological mineralization of structures in the spine, however, are unknown. Using the Abcc6−/− mouse model of PXE, we investigated age-dependent changes in the vertebral bone and intervertebral disc. Abcc6−/− mice exhibited diminished trabecular bone quality parameters at 7 months, which remained significantly lower than the wild-type mice at 18 months of age. Abcc6−/− vertebrae showed increased TRAP staining along with decreased TNAP staining, suggesting an enhanced bone resorption as well as decreased bone formation. Surprisingly, however, loss of ABCC6 resulted only in a mild, aging disc phenotype without evidence of dystrophic mineralization. Finally, we tested the utility of oral K3Citrate to treat the vertebral phenotype since it is shown to regulate hydroxyapatite mechanical behavior. The treatment resulted in inhibition of the osteoclastic response and an early improvement in mechanical properties of the bone underscoring the promise of potassium citrate as a therapeutic agent. Our data suggest that although ectopic mineralization is tightly regulated in the disc, loss of ABCC6 compromises vertebral bone quality and dysregulates osteoblast-osteoclast coupling.
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Affiliation(s)
- Paige K. Boneski
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, United States
| | - Vedavathi Madhu
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, United States
| | - Ryan E. Tomlinson
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, United States
| | - Irving M. Shapiro
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, United States
| | - Koen van de Wetering
- Department of Dermatology and Cutaneous Biology, Jefferson Institute of Molecular Medicine and PXE International Center of Excellence in Research and Clinical Care, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, United States
| | - Makarand V. Risbud
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, United States
- *Correspondence: Makarand V. Risbud,
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22
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Song M, Zhang Y, Sun Y, Kong M, Han S, Wang C, Wang Y, Xu D, Tu Q, Zhu K, Sun C, Li G, Zhao H, Ma X. Inhibition of RhoA/MRTF-A signaling alleviates nucleus pulposus fibrosis induced by mechanical stress overload. Connect Tissue Res 2022; 63:53-68. [PMID: 34420462 DOI: 10.1080/03008207.2021.1952193] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE/AIM : Intervertebral disc degeneration (IDD) is the leading cause of lower back pain, and clinically useful drugs for IDD are unavailable. Mechanical stress overload-induced fibrosis plays a critical role in IDD. RhoA/MRTF-A signaling is known to regulate tissue fibrosis; however, the effect of RhoA/MRTF-A on the development of IDD is unclear. MATERIALS AND METHODS : The expression of aggrecan, collagen I, collagen II, MMP-12, CTGF, and MRTF-A in nucleus pulposus (NP) samples from IDD patients and controls was detected by immunohistochemical staining. Primary nucleus pulposus cells (NPCs) were isolated and cultured to establish an overload strain model treated with or without CCG-1423. The protein levels of RhoA, ROCK2, MRTF-A, CTGF, and MMP-12 as well as fibrosis-associated proteins were detected by western blotting and immunofluorescence. RESULTS : Collagen I, MMP-12, and CTGF were significantly upregulated, and aggrecan and collagen II were significantly downregulated in the IDD samples. The cellular localization of MRTF-A was associated with intervertebral disc (IVD) degeneration. Overloaded strain enhanced the nuclear translocation of MRTF-A and changed the NPC morphology from spindle-shaped to long strips. Additional experiments showed that RhoA, ROCK2, MRTF-A, SRF, MMP-12, and CTGF were upregulated; however, aggrecan and collagen II were downregulated in NPCs under overload strain. CCG-1423, a RhoA/MRTF-A pathway inhibitor, reversed strain-induced fibrosis. CONCLUSION : Mechanical stress activates RhoA/MRTF-A signaling to promote extracellular matrix (ECM) degeneration in the NP, which is associated with the development of IDD. Our findings suggest that the RhoA/MRTF-A inhibitor CCG-1423 can alleviate NPC degeneration caused by overload stress and has potential as a therapeutic agent for IDD.
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Affiliation(s)
- Mengxiong Song
- Department of Orthopaedic Surgery, Minhang Hospital, Fudan University, Shanghai, China
| | - Yiran Zhang
- Shandong Institute of Orthopaedics and Traumatology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yi Sun
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Meng Kong
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shuo Han
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chao Wang
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yan Wang
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Derong Xu
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Qihao Tu
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Kai Zhu
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chong Sun
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Guanghui Li
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Han Zhao
- Department of Pathology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xuexiao Ma
- Department of Orthopaedics, Affiliated Hospital of Qingdao University, Qingdao, China
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Zhou S, Li Y, Wu X, Wang X, Yu R, Zhang Y. Construction of a Circ_0020407/Circ_0069323-Mir-486-5p-Pten/Foxo1 interaction network related to intervertebral disc degeneration. Minerva Med 2021; 113:737-741. [PMID: 34825812 DOI: 10.23736/s0026-4806.21.07874-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Suzhe Zhou
- Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, China.,Hefei BOE Hospital, Hefei, China
| | - Yongjin Li
- Department of Minimally Invasive Spine Surgery, Tianjin Hospital, Tianjin, China
| | - Xiaojing Wu
- Department of Surgery Critical Care Medicine, Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | - Xuke Wang
- Department of Minimally Invasive Spine Surgery, Luoyang Orthopedic-Traumatological Hospital, Luoyang, China
| | - Runze Yu
- Department of Orthopedics, Anhui No.2 Provincial People's Hospital, Hefei, China -
| | - Yubing Zhang
- Department of Orthopedics, Anhui No.2 Provincial People's Hospital, Hefei, China
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Li C, Bai Q, Lai Y, Tian J, Li J, Sun X, Zhao Y. Advances and Prospects in Biomaterials for Intervertebral Disk Regeneration. Front Bioeng Biotechnol 2021; 9:766087. [PMID: 34746112 PMCID: PMC8569141 DOI: 10.3389/fbioe.2021.766087] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Low-back and neck-shoulder pains caused by intervertebral disk degeneration are highly prevalent among middle-aged and elderly people globally. The main therapy method for intervertebral disk degeneration is surgical intervention, including interbody fusion, disk replacement, and diskectomy. However, the stress changes caused by traditional fusion surgery are prone to degeneration of adjacent segments, while non-fusion surgery has problems, such as ossification of artificial intervertebral disks. To overcome these drawbacks, biomaterials that could endogenously regenerate the intervertebral disk and restore the biomechanical function of the intervertebral disk is imperative. Intervertebral disk is a fibrocartilaginous tissue, primarily comprising nucleus pulposus and annulus fibrosus. Nucleus pulposus (NP) contains high water and proteoglycan, and its main function is absorbing compressive forces and dispersing loads from physical activities to other body parts. Annulus fibrosus (AF) is a multilamellar structure that encloses the NP, comprises water and collagen, and supports compressive and shear stress during complex motion. Therefore, different biomaterials and tissue engineering strategies are required for the functional recovery of NP and AF based on their structures and function. Recently, great progress has been achieved on biomaterials for NP and AF made of functional polymers, such as chitosan, collagen, polylactic acid, and polycaprolactone. However, scaffolds regenerating intervertebral disk remain unexplored. Hence, several tissue engineering strategies based on cell transplantation and growth factors have been extensively researched. In this review, we summarized the functional polymers and tissue engineering strategies of NP and AF to endogenously regenerate degenerative intervertebral disk. The perspective and challenges of tissue engineering strategies using functional polymers, cell transplantation, and growth factor for generating degenerative intervertebral disks were also discussed.
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Affiliation(s)
- Chunxu Li
- Department of Orthopaedics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Qiushi Bai
- Department of Orthopaedics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Yuxiao Lai
- Centre for Translational Medicine Research and Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Jingjing Tian
- Medical Science Research Center, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Jiahao Li
- Department of Orthopaedics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaodan Sun
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, China
| | - Yu Zhao
- Department of Orthopaedics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
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25
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Novais EJ, Tran VA, Johnston SN, Darris KR, Roupas AJ, Sessions GA, Shapiro IM, Diekman BO, Risbud MV. Long-term treatment with senolytic drugs Dasatinib and Quercetin ameliorates age-dependent intervertebral disc degeneration in mice. Nat Commun 2021; 12:5213. [PMID: 34480023 PMCID: PMC8417260 DOI: 10.1038/s41467-021-25453-2] [Citation(s) in RCA: 149] [Impact Index Per Article: 49.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 08/04/2021] [Indexed: 02/07/2023] Open
Abstract
Intervertebral disc degeneration is highly prevalent within the elderly population and is a leading cause of chronic back pain and disability. Due to the link between disc degeneration and senescence, we explored the ability of the Dasatinib and Quercetin drug combination (D + Q) to prevent an age-dependent progression of disc degeneration in mice. We treated C57BL/6 mice beginning at 6, 14, and 18 months of age, and analyzed them at 23 months of age. Interestingly, 6- and 14-month D + Q cohorts show lower incidences of degeneration, and the treatment results in a significant decrease in senescence markers p16INK4a, p19ARF, and SASP molecules IL-6 and MMP13. Treatment also preserves cell viability, phenotype, and matrix content. Although transcriptomic analysis shows disc compartment-specific effects of the treatment, cell death and cytokine response pathways are commonly modulated across tissue types. Results suggest that senolytics may provide an attractive strategy to mitigating age-dependent disc degeneration.
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Affiliation(s)
- Emanuel J. Novais
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, USA ,grid.10328.380000 0001 2159 175XLife and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal ,grid.10328.380000 0001 2159 175XICVS/3B’s—PT Government Associate Laboratory, Braga, Portugal
| | - Victoria A. Tran
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, USA
| | - Shira N. Johnston
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, USA
| | - Kayla R. Darris
- grid.10698.360000000122483208Thurston Arthritis Research Center, University of North Carolina School of Medicine, Chapel Hill, NC USA ,grid.40803.3f0000 0001 2173 6074Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, and North Carolina State University, Raleigh, NC USA
| | - Alex J. Roupas
- grid.10698.360000000122483208Thurston Arthritis Research Center, University of North Carolina School of Medicine, Chapel Hill, NC USA ,grid.40803.3f0000 0001 2173 6074Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, and North Carolina State University, Raleigh, NC USA
| | - Garrett A. Sessions
- grid.10698.360000000122483208Thurston Arthritis Research Center, University of North Carolina School of Medicine, Chapel Hill, NC USA ,grid.40803.3f0000 0001 2173 6074Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, and North Carolina State University, Raleigh, NC USA
| | - Irving M. Shapiro
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, USA
| | - Brian O. Diekman
- grid.10698.360000000122483208Thurston Arthritis Research Center, University of North Carolina School of Medicine, Chapel Hill, NC USA ,grid.40803.3f0000 0001 2173 6074Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, and North Carolina State University, Raleigh, NC USA
| | - Makarand V. Risbud
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, USA
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26
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The role of HIF proteins in maintaining the metabolic health of the intervertebral disc. Nat Rev Rheumatol 2021; 17:426-439. [PMID: 34083809 PMCID: PMC10019070 DOI: 10.1038/s41584-021-00621-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2021] [Indexed: 01/18/2023]
Abstract
The physiologically hypoxic intervertebral disc and cartilage rely on the hypoxia-inducible factor (HIF) family of transcription factors to mediate cellular responses to changes in oxygen tension. During homeostatic development, oxygen-dependent prolyl hydroxylases, circadian clock proteins and metabolic intermediates control the activities of HIF1 and HIF2 in these tissues. Mechanistically, HIF1 is the master regulator of glycolytic metabolism and cytosolic lactate levels. In addition, HIF1 regulates mitochondrial metabolism by promoting flux through the tricarboxylic acid cycle, inhibiting downsteam oxidative phosphorylation and controlling mitochondrial health through modulation of the mitophagic pathway. Accumulation of metabolic intermediates from HIF-dependent processes contribute to intracellular pH regulation in the disc and cartilage. Namely, to prevent changes in intracellular pH that could lead to cell death, HIF1 orchestrates a bicarbonate buffering system in the disc, controlled by carbonic anhydrase 9 (CA9) and CA12, sodium bicarbonate cotransporters and an intracellular H+/lactate efflux mechanism. In contrast to HIF1, the role of HIF2 remains elusive; in disorders of the disc and cartilage, its function has been linked to both anabolic and catabolic pathways. The current knowledge of hypoxic cell metabolism and regulation of HIF1 activity provides a strong basis for the development of future therapies designed to repair the degenerative disc.
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27
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Melgoza IP, Chenna SS, Tessier S, Zhang Y, Tang SY, Ohnishi T, Novais EJ, Kerr GJ, Mohanty S, Tam V, Chan WCW, Zhou C, Zhang Y, Leung VY, Brice AK, Séguin CA, Chan D, Vo N, Risbud MV, Dahia CL. Development of a standardized histopathology scoring system using machine learning algorithms for intervertebral disc degeneration in the mouse model-An ORS spine section initiative. JOR Spine 2021; 4:e1164. [PMID: 34337338 PMCID: PMC8313179 DOI: 10.1002/jsp2.1164] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/01/2021] [Accepted: 06/07/2021] [Indexed: 12/28/2022] Open
Abstract
Mice have been increasingly used as preclinical model to elucidate mechanisms and test therapeutics for treating intervertebral disc degeneration (IDD). Several intervertebral disc (IVD) histological scoring systems have been proposed, but none exists that reliably quantitate mouse disc pathologies. Here, we report a new robust quantitative mouse IVD histopathological scoring system developed by building consensus from the spine community analyses of previous scoring systems and features noted on different mouse models of IDD. The new scoring system analyzes 14 key histopathological features from nucleus pulposus (NP), annulus fibrosus (AF), endplate (EP), and AF/NP/EP interface regions. Each feature is categorized and scored; hence, the weight for quantifying the disc histopathology is equally distributed and not driven by only a few features. We tested the new histopathological scoring criteria using images of lumbar and coccygeal discs from different IDD models of both sexes, including genetic, needle-punctured, static compressive models, and natural aging mice spanning neonatal to old age stages. Moreover, disc sections from common histological preparation techniques and stains including H&E, SafraninO/Fast green, and FAST were analyzed to enable better cross-study comparisons. Fleiss's multi-rater agreement test shows significant agreement by both experienced and novice multiple raters for all 14 features on several mouse models and sections prepared using various histological techniques. The sensitivity and specificity of the new scoring system was validated using artificial intelligence and supervised and unsupervised machine learning algorithms, including artificial neural networks, k-means clustering, and principal component analysis. Finally, we applied the new scoring system on established disc degeneration models and demonstrated high sensitivity and specificity of histopathological scoring changes. Overall, the new histopathological scoring system offers the ability to quantify histological changes in mouse models of disc degeneration and regeneration with high sensitivity and specificity.
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Affiliation(s)
- Itzel Paola Melgoza
- Orthopedic Soft Tissue Research ProgramHospital for Special SurgeryNew York CityNew YorkUSA
| | - Srish S. Chenna
- Orthopedic Soft Tissue Research ProgramHospital for Special SurgeryNew York CityNew YorkUSA
| | - Steven Tessier
- Department of Orthopaedic SurgerySidney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA
| | - Yejia Zhang
- University of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Simon Y. Tang
- Department of Orthopaedic SurgeryWashington University in St LouisMissouriUSA
| | - Takashi Ohnishi
- Department of Orthopaedic SurgerySidney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA
- Department of Orthopaedic SurgeryFaculty of Medicine and Graduate School of Medicine, Hokkaido UniversitySapporoJapan
| | - Emanuel José Novais
- Department of Orthopaedic SurgerySidney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA
- Lewis Katz School of Medicine at Temple UniversityPhiladelphiaPennsylvaniaUSA
| | - Geoffrey J. Kerr
- Department of Physiology & PharmacologyBone & Joint Institute, University of Western OntarioLondonOntarioCanada
| | | | - Vivian Tam
- School of Biomedical SciencesThe University of Hong KongPokfulamHong Kong
| | - Wilson C. W. Chan
- School of Biomedical SciencesThe University of Hong KongPokfulamHong Kong
- Department of Orthopaedic and TraumatologyThe University of Hong Kong‐Shenzhen HospitalShenzhenGuangdongChina
| | - Chao‐Ming Zhou
- Department of Orthopaedic SurgeryUniversity of PittsburghPennsylvaniaUSA
| | - Ying Zhang
- School of Biomedical SciencesThe University of Hong KongPokfulamHong Kong
| | - Victor Y. Leung
- Department of Orthopaedics and TraumatologyThe University of Hong KongPokfulamHong Kong
| | | | - Cheryle A. Séguin
- Department of Physiology & PharmacologyBone & Joint Institute, University of Western OntarioLondonOntarioCanada
| | - Danny Chan
- School of Biomedical SciencesThe University of Hong KongPokfulamHong Kong
- Department of Orthopaedic and TraumatologyThe University of Hong Kong‐Shenzhen HospitalShenzhenGuangdongChina
| | - Nam Vo
- Department of Orthopaedic SurgeryUniversity of PittsburghPennsylvaniaUSA
| | - Makarand V. Risbud
- Department of Orthopaedic SurgerySidney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA
| | - Chitra L. Dahia
- Orthopedic Soft Tissue Research ProgramHospital for Special SurgeryNew York CityNew YorkUSA
- Department of Cell & Developmental BiologyWeill Cornell Medicine Graduate School of Medical SciencesNew York CityNew YorkUSA
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28
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Articular Chondrocyte Phenotype Regulation through the Cytoskeleton and the Signaling Processes That Originate from or Converge on the Cytoskeleton: Towards a Novel Understanding of the Intersection between Actin Dynamics and Chondrogenic Function. Int J Mol Sci 2021; 22:ijms22063279. [PMID: 33807043 PMCID: PMC8004672 DOI: 10.3390/ijms22063279] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 02/08/2023] Open
Abstract
Numerous studies have assembled a complex picture, in which extracellular stimuli and intracellular signaling pathways modulate the chondrocyte phenotype. Because many diseases are mechanobiology-related, this review asked to what extent phenotype regulators control chondrocyte function through the cytoskeleton and cytoskeleton-regulating signaling processes. Such information would generate leverage for advanced articular cartilage repair. Serial passaging, pro-inflammatory cytokine signaling (TNF-α, IL-1α, IL-1β, IL-6, and IL-8), growth factors (TGF-α), and osteoarthritis not only induce dedifferentiation but also converge on RhoA/ROCK/Rac1/mDia1/mDia2/Cdc42 to promote actin polymerization/crosslinking for stress fiber (SF) formation. SF formation takes center stage in phenotype control, as both SF formation and SOX9 phosphorylation for COL2 expression are ROCK activity-dependent. Explaining how it is molecularly possible that dedifferentiation induces low COL2 expression but high SF formation, this review theorized that, in chondrocyte SOX9, phosphorylation by ROCK might effectively be sidelined in favor of other SF-promoting ROCK substrates, based on a differential ROCK affinity. In turn, actin depolymerization for redifferentiation would “free-up” ROCK to increase COL2 expression. Moreover, the actin cytoskeleton regulates COL1 expression, modulates COL2/aggrecan fragment generation, and mediates a fibrogenic/catabolic expression profile, highlighting that actin dynamics-regulating processes decisively control the chondrocyte phenotype. This suggests modulating the balance between actin polymerization/depolymerization for therapeutically controlling the chondrocyte phenotype.
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29
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Ge Q, Ying J, Shi Z, Mao Q, Jin H, Wang PE, Chen J, Yuan W, Tong P, Li J. Chlorogenic Acid retards cartilaginous endplate degeneration and ameliorates intervertebral disc degeneration via suppressing NF-κB signaling. Life Sci 2021; 274:119324. [PMID: 33711382 DOI: 10.1016/j.lfs.2021.119324] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/19/2021] [Accepted: 02/27/2021] [Indexed: 02/07/2023]
Abstract
AIMS Intervertebral Disc Degeneration (IDD) is a key factor involved in low back pain (LBP) which affects approximately 540 million individuals worldwide. Chlorogenic Acid (CGA), a natural compound, exerts anti-inflammatory property in several diseases. Here, we aim to investigate the biological effect of CGA on IDD and explore the underlying mechanism. MATERIALS AND METHODS Lumbar spine instability (LSI) model in mice was utilized to mimic process of IDD. The effects of CGA in response to LSI were evaluated by luminescent imaging, micro-CT, histomorphology, and immunohistochemistry in vivo. Besides, the cytotoxicity of CGA on chondrocytes was detected by cell counting kit-8 (CCK-8) and the biological effects were assessed by polymerase chain reaction (PCR) in vitro. KEY FINDINGS We found that CGA treatment dramatically suppressed the NF-κB activity in LSI mice. Moreover, administration of CGA mitigated cartilaginous endplate degeneration and postponed IDD development accompanying a decrease of inflammatory and catabolic mediators. Specifically, CGA ameliorated endplate degeneration might be related to its protective effects against endplate chondrocytes apoptosis and trans-differentiation. We further elucidated that CGA exerted these biological effects mainly by repressing NF-κB signaling in cartilage endplate. SIGNIFICANCE Our study has illustrated, for the first time, the curative effects as well as the latent mechanism of CGA in IDD and our results suggested that CGA administration might be used as an alternative therapy for IDD.
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Affiliation(s)
- Qinwen Ge
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jun Ying
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; Department of Orthopaedic Surgery, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, China
| | - Zhenyu Shi
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; The First College of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Qiang Mao
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; Department of Orthopaedic Surgery, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, China
| | - Hongting Jin
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Ping-Er Wang
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jiali Chen
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Wenhua Yuan
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Peijian Tong
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; Department of Orthopaedic Surgery, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, China.
| | - Ju Li
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China; Department of Orthopaedic Surgery, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, China.
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Novais EJ, Choi H, Madhu V, Suyama K, Anjo SI, Manadas B, Shapiro IM, Salgado AJ, Risbud MV. Hypoxia and Hypoxia-Inducible Factor-1α Regulate Endoplasmic Reticulum Stress in Nucleus Pulposus Cells: Implications of Endoplasmic Reticulum Stress for Extracellular Matrix Secretion. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:487-502. [PMID: 33307037 PMCID: PMC7927276 DOI: 10.1016/j.ajpath.2020.11.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/03/2020] [Accepted: 11/24/2020] [Indexed: 12/20/2022]
Abstract
Endoplasmic reticulum (ER) stress is shown to promote nucleus pulposus (NP) cell apoptosis and intervertebral disc degeneration. However, little is known about ER stress regulation by the hypoxic disc microenvironment and its contribution to extracellular matrix homeostasis. NP cells were cultured under hypoxia (1% partial pressure of oxygen) to assess ER stress status, and gain-of-function and loss-of-function approaches were used to assess the role of hypoxia-inducible factor (HIF)-1α in this pathway. In addition, the contribution of ER stress induction on the NP cell secretome was assessed by a nontargeted quantitative proteomic analysis by sequential windowed data independent acquisition of the total high-resolution mass spectra-mass spectrometry. NP cells exhibited a lower ER stress burden under hypoxia. Knockdown of HIF-1α increased C/EBP homologous protein, protein kinase RNA-like endoplasmic reticulum kinase (PERK), and activating transcription factor 6 (ATF6) levels, whereas HIF-1α stabilization decreased the expression of ER stress markers Ddit3, Hsp5a, Atf6, and Eif2a. Interestingly, ER stress inducers tunicamycin and thapsigargin induced HIF-1α activity under hypoxia while promoting the unfolded protein response. NP cell secretome analysis demonstrated an impact of ER stress induction on extracellular matrix secretion, with decreases in collagens and cell adhesion-related proteins. Moreover, analysis of transcriptomic data of NP tissues from aged mice and degenerated human discs showed higher levels of unfolded protein response markers and decreased levels of matrix components. Our study shows, for the first time, that hypoxia and HIF-1α attenuate ER stress responses in NP cells, and ER stress promotes inefficient extracellular matrix secretion under hypoxia.
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Affiliation(s)
- Emanuel J Novais
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania; Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal; Life and Health Sciences Research Institute/Biomaterials, Biodegradables and Biomimetics (ICVS/3B's) - PT Government Associate Laboratory, Braga, Portugal
| | - Hyowon Choi
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Vedavathi Madhu
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Kaori Suyama
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Department of Anatomy and Cellular Biology, Tokai University School of Medicine, Isehara, Japan
| | - Sandra I Anjo
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Bruno Manadas
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Irving M Shapiro
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - António J Salgado
- Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal; Life and Health Sciences Research Institute/Biomaterials, Biodegradables and Biomimetics (ICVS/3B's) - PT Government Associate Laboratory, Braga, Portugal
| | - Makarand V Risbud
- Department of Orthopedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania; Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania.
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Snuggs JW, Tessier S, Bunning RAB, Shapiro IM, Risbud MV, Le Maitre CL. TonEBP regulates the hyperosmotic expression of aquaporin 1 and 5 in the intervertebral disc. Sci Rep 2021; 11:3164. [PMID: 33542263 PMCID: PMC7862284 DOI: 10.1038/s41598-021-81838-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 12/22/2020] [Indexed: 01/30/2023] Open
Abstract
The central region of the intervertebral disc (IVD) is rich in proteoglycans, leading to a hyperosmotic environment, which fluctuates with daily loading. The cells of the nucleus pulposus (NP cells) have adapted to this environment via the function of tonicity enhancer binding protein (TonEBP), and NP cells have been shown to express several water channels known as aquaporins (AQP). We have previously shown that AQP1 and 5 decrease during IVD degeneration. Here, the regulation of AQP1 and 5 by hyperosmotic conditions and the role of TonEBP in this regulation was investigated. AQP1 and 5 gene expression was upregulated by hyperosmotic conditions mimicking the osmolality of the healthy IVD, which was abrogated by TonEBP knockdown. Furthermore, AQP1 and 5 immunopositivity was significantly reduced in TonEBPΔ/Δ E17.5 mice when compared with wildtype controls, indicating in vivo expression of AQP1 and 5 is controlled at least in part by TonEBP. This hyperosmotic regulation of AQP1 and 5 could help to explain the decreased AQP1 and 5 expression during degeneration, when the osmolality of the NP decreases. Together this data suggests that TonEBP-regulated osmo-adaptation may be disrupted during IVD degeneration when the expression of both AQPs is reduced.
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Affiliation(s)
- J. W. Snuggs
- grid.5884.10000 0001 0303 540XBiomolecular Sciences Research Centre, Sheffield Hallam University, City Campus, Howard Street, Sheffield, S1 1WB UK
| | - S. Tessier
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA USA
| | - R. A. B. Bunning
- grid.5884.10000 0001 0303 540XBiomolecular Sciences Research Centre, Sheffield Hallam University, City Campus, Howard Street, Sheffield, S1 1WB UK
| | - I. M. Shapiro
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
| | - M. V. Risbud
- grid.265008.90000 0001 2166 5843Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA USA ,grid.265008.90000 0001 2166 5843Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
| | - C. L. Le Maitre
- grid.5884.10000 0001 0303 540XBiomolecular Sciences Research Centre, Sheffield Hallam University, City Campus, Howard Street, Sheffield, S1 1WB UK
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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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Baumgartner L, Wuertz-Kozak K, Le Maitre CL, Wignall F, Richardson SM, Hoyland J, Ruiz Wills C, González Ballester MA, Neidlin M, Alexopoulos LG, Noailly J. Multiscale Regulation of the Intervertebral Disc: Achievements in Experimental, In Silico, and Regenerative Research. Int J Mol Sci 2021; 22:E703. [PMID: 33445782 PMCID: PMC7828304 DOI: 10.3390/ijms22020703] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/22/2020] [Accepted: 12/24/2020] [Indexed: 12/17/2022] Open
Abstract
Intervertebral disc (IVD) degeneration is a major risk factor of low back pain. It is defined by a progressive loss of the IVD structure and functionality, leading to severe impairments with restricted treatment options due to the highly demanding mechanical exposure of the IVD. Degenerative changes in the IVD usually increase with age but at an accelerated rate in some individuals. To understand the initiation and progression of this disease, it is crucial to identify key top-down and bottom-up regulations' processes, across the cell, tissue, and organ levels, in health and disease. Owing to unremitting investigation of experimental research, the comprehension of detailed cell signaling pathways and their effect on matrix turnover significantly rose. Likewise, in silico research substantially contributed to a holistic understanding of spatiotemporal effects and complex, multifactorial interactions within the IVD. Together with important achievements in the research of biomaterials, manifold promising approaches for regenerative treatment options were presented over the last years. This review provides an integrative analysis of the current knowledge about (1) the multiscale function and regulation of the IVD in health and disease, (2) the possible regenerative strategies, and (3) the in silico models that shall eventually support the development of advanced therapies.
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Affiliation(s)
- Laura Baumgartner
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
| | - Karin Wuertz-Kozak
- Department of Biomedical Engineering, Rochester Institute of Technology (RIT), Rochester, NY 14623, USA;
- Schön Clinic Munich Harlaching, Spine Center, Academic Teaching Hospital and Spine Research Institute of the Paracelsus Medical University Salzburg (Austria), 81547 Munich, Germany
| | - Christine L. Le Maitre
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield S1 1WB, UK;
| | - Francis Wignall
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Stephen M. Richardson
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Judith Hoyland
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Carlos Ruiz Wills
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
| | - Miguel A. González Ballester
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
- Catalan Institution for Research and Advanced Studies (ICREA), Pg. Lluis Companys 23, 08010 Barcelona, Spain
| | - Michael Neidlin
- Department of Mechanical Engineering, National Technical University of Athens, 15780 Athens, Greece; (M.N.); (L.G.A.)
| | - Leonidas G. Alexopoulos
- Department of Mechanical Engineering, National Technical University of Athens, 15780 Athens, Greece; (M.N.); (L.G.A.)
| | - Jérôme Noailly
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
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Madhu V, Guntur AR, Risbud MV. Role of autophagy in intervertebral disc and cartilage function: implications in health and disease. Matrix Biol 2020; 100-101:207-220. [PMID: 33301899 DOI: 10.1016/j.matbio.2020.12.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/02/2020] [Accepted: 12/03/2020] [Indexed: 12/12/2022]
Abstract
The intervertebral disc and cartilage are specialized, extracellular matrix-rich tissues critical for absorbing mechanical loads, providing flexibility to the joints, and longitudinal growth in the case of growth plate cartilage. Specialized niche conditions in these tissues, such as hypoxia, are critical in regulating cellular activities including autophagy, a lysosomal degradation pathway that promotes cell survival. Mounting evidence suggests that dysregulation of autophagic pathways underscores many skeletal pathologies affecting the spinal column, articular and growth plate cartilages. Many lysosomal storage disorders characterized by the accumulation of partially degraded glycosaminoglycans (GAGs) due to the lysosomal dysfunction thus affect skeletal tissues and result in altered ECM structure. Likewise, pathologies that arise from mutations in genes encoding ECM proteins and ECM processing, folding, and post-translational modifications, result in accumulation of misfolded proteins in the ER, ER stress and autophagy dysregulation. These conditions evidence reduced secretion of ECM proteins and/or increased secretion of mutant proteins, thereby impairing matrix quality and the integrity of affected skeletal tissues and causing a lack of growth and degeneration. In this review, we discuss the role of autophagy and mechanisms of its regulation in the intervertebral disc and cartilages, as well as how dysregulation of autophagic pathways affects these skeletal tissues.
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Affiliation(s)
- Vedavathi Madhu
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Anyonya R Guntur
- Center for Molecular Medicine, Maine Medical Center Research Institute, Scarborough, ME, USA; Tufts University School of Medicine, Tufts University, Boston, MA USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA; Cell Biology and Regenerative Medicine Graduate Program, Thomas Jefferson University, Philadelphia, PA, USA.
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35
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Tsingas M, Ottone OK, Haseeb A, Barve RA, Shapiro IM, Lefebvre V, Risbud MV. Sox9 deletion causes severe intervertebral disc degeneration characterized by apoptosis, matrix remodeling, and compartment-specific transcriptomic changes. Matrix Biol 2020; 94:110-133. [PMID: 33027692 DOI: 10.1016/j.matbio.2020.09.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/30/2020] [Accepted: 09/30/2020] [Indexed: 12/27/2022]
Abstract
SOX9 plays an important role in chondrocyte differentiation and, in the developing axial skeleton, maintains the notochord and the demarcation of intervertebral disc compartments. Diminished expression is linked to campomelic dysplasia, resulting in severe scoliosis and progressive disc degeneration. However, the specific functions of SOX9 in the adult spinal column and disc are largely unknown. Accordingly, employing a strategy to conditionally delete Sox9 in Acan-expressing cells (AcanCreERT2Sox9fl/fl), we delineated these functions in the adult intervertebral disc. AcanCreERT2Sox9fl/fl mice (Sox9cKO) showed extensive and progressive remodeling of the extracellular matrix in nucleus pulposus (NP) and annulus fibrosus (AF), consistent with human disc degeneration. Progressive degeneration of the cartilaginous endplates (EP) was also evident in Sox9cKO mice, and it preceded morphological changes seen in the NP and AF compartments. Fate mapping using tdTomato reporter, EdU chase, and quantitative immunohistological studies demonstrated that SOX9 is crucial for disc cell survival and phenotype maintenance. Microarray analysis showed that Sox9 regulated distinct compartment-specific transcriptomic landscapes, with prominent contributions to the ECM, cytoskeleton-related, and metabolic pathways in the NP and ion transport, the cell cycle, and signaling pathways in the AF. In summary, our work provides new insights into disc degeneration in Sox9cKO mice at the cellular, molecular, and transcriptional levels, underscoring tissue-specific roles of this transcription factor. Our findings may direct future cell therapies targeting SOX9 to mitigate disc degeneration.
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Affiliation(s)
- Maria Tsingas
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Olivia K Ottone
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Abdul Haseeb
- Department of Surgery/Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Ruteja A Barve
- Department of Genetics, Genome Technology Access Centre at the McDonnell Genome Institute, Washington University, School of Medicine, St. Louis, MO 63110, USA
| | - Irving M Shapiro
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Véronique Lefebvre
- Department of Surgery/Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA; Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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36
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Veras MA, Lim YJ, Kuljanin M, Lajoie GA, Urquhart BL, Séguin CA. Protocol for parallel proteomic and metabolomic analysis of mouse intervertebral disc tissues. JOR Spine 2020; 3:e1099. [PMID: 33015574 PMCID: PMC7524214 DOI: 10.1002/jsp2.1099] [Citation(s) in RCA: 4] [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] [Received: 01/30/2020] [Revised: 04/25/2020] [Accepted: 05/14/2020] [Indexed: 01/07/2023] Open
Abstract
The comprehensiveness of data collected by "omics" modalities has demonstrated the ability to drastically transform our understanding of the molecular mechanisms of chronic, complex diseases such as musculoskeletal pathologies, how biomarkers are identified, and how therapeutic targets are developed. Standardization of protocols will enable comparisons between findings reported by multiple research groups and move the application of these technologies forward. Herein, we describe a protocol for parallel proteomic and metabolomic analysis of mouse intervertebral disc (IVD) tissues, building from the combined expertise of our collaborative team. This protocol covers dissection of murine IVD tissues, sample isolation, and data analysis for both proteomics and metabolomics applications. The protocol presented below was optimized to maximize the utility of a mouse model for "omics" applications, accounting for the challenges associated with the small starting quantity of sample due to small tissue size as well as the extracellular matrix-rich nature of the tissue.
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Affiliation(s)
- Matthew A Veras
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry The University of Western Ontario London Ontario Canada
- Bone and Joint Institute The University of Western Ontario London Ontario Canada
| | - Yong J Lim
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry The University of Western Ontario London Ontario Canada
| | - Miljan Kuljanin
- Department of Cell Biology Harvard Medical School Boston Massachusetts USA
| | - Gilles A Lajoie
- Department of Biochemistry, Schulich School of Medicine & Dentistry The University of Western Ontario London Ontario Canada
| | - Bradley L Urquhart
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry The University of Western Ontario London Ontario Canada
| | - Cheryle A Séguin
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry The University of Western Ontario London Ontario Canada
- Bone and Joint Institute The University of Western Ontario London Ontario Canada
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37
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Madhu V, Boneski PK, Silagi E, Qiu Y, Kurland I, Guntur AR, Shapiro IM, Risbud MV. Hypoxic Regulation of Mitochondrial Metabolism and Mitophagy in Nucleus Pulposus Cells Is Dependent on HIF-1α-BNIP3 Axis. J Bone Miner Res 2020; 35:1504-1524. [PMID: 32251541 PMCID: PMC7778522 DOI: 10.1002/jbmr.4019] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 02/28/2020] [Accepted: 03/15/2020] [Indexed: 12/31/2022]
Abstract
Nucleus pulposus (NP) cells reside in an avascular and hypoxic microenvironment of the intervertebral disc and are predominantly glycolytic due to robust HIF-1 activity. It is generally thought that NP cells contain few functional mitochondria compared with cells that rely on oxidative metabolism. Consequently, the contribution of mitochondria to NP cell metabolism and the role of hypoxia and HIF-1 in mitochondrial homeostasis is poorly understood. Using mitoQC reporter mice, we show for the first time to our knowledge that NP cell mitochondria undergo age-dependent mitophagy in vivo. Mechanistically, in vitro studies suggest that, under hypoxic conditions, mitochondria in primary NP cells undergo HIF-1α-dependent fragmentation, controlled by modulating the levels of key proteins DRP1 and OPA1 that are involved in mitochondrial fission and fusion, respectively. Seahorse assays and steady state metabolic profiling coupled with [1-2-13 C]-glucose flux analysis revealed that in hypoxia, HIF-1α regulated metabolic flux through coordinating glycolysis and the mitochondrial TCA cycle interactions, thereby controlling the overall biosynthetic capacity of NP cells. We further show that hypoxia and HIF-1α trigger mitophagy in NP cells through the mitochondrial translocation of BNIP3, an inducer of receptor-mediated mitophagy. Surprisingly, however, loss of HIF-1α in vitro and analysis of NP-specific HIF-1α null mice do not show a decrease in mitophagic flux in NP cells but a compensatory increase in NIX and PINK1-Parkin pathways with higher mitochondrial number. Taken together, our studies provide novel mechanistic insights into the complex interplay between hypoxia and HIF-1α signaling on the mitochondrial metabolism and quality control in NP cells. © 2020 American Society for Bone and Mineral Research.
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Affiliation(s)
- Vedavathi Madhu
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Paige K Boneski
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Elizabeth Silagi
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA.,Cell Biology and Regenerative Medicine Graduate Program, Thomas Jefferson University, Philadelphia, PA, USA
| | - Yunping Qiu
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Irwin Kurland
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Anyonya R Guntur
- Center for Molecular Medicine, Maine Medical Center Research Institute, Scarborough, ME, USA
| | - Irving M Shapiro
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA.,Cell Biology and Regenerative Medicine Graduate Program, Thomas Jefferson University, Philadelphia, PA, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA.,Cell Biology and Regenerative Medicine Graduate Program, Thomas Jefferson University, Philadelphia, PA, USA
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38
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Tessier S, Risbud MV. Understanding embryonic development for cell-based therapies of intervertebral disc degeneration: Toward an effort to treat disc degeneration subphenotypes. Dev Dyn 2020; 250:302-317. [PMID: 32564440 DOI: 10.1002/dvdy.217] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/09/2020] [Accepted: 06/14/2020] [Indexed: 12/19/2022] Open
Abstract
Chronic low back and neck pain are associated with intervertebral disc degeneration and are major contributors to the global burden of disability. New evidence now suggests that disc degeneration comprises a spectrum of subphenotypes influenced by genetic background, age, and environmental factors, which may be contributing to the mixed outcomes seen in clinical trials of cell-based therapies that aim to treat disc degeneration. This problem is further compounded by the fact that disc degeneration and aging coincide with an exhaustion of endogenous progenitor cells, imposing limitations on the regenerative capacity of the disc. At the bench-side, current work is focused on applying our knowledge of embryonic disc development to direct and refine differentiation of adult and human-induced pluripotent stem cells into notochord-like and nucleus pulposus-like cells for use in novel cell-based therapies. Accordingly, this review presents the salient features of intervertebral disc development, post-natal maintenance, and regeneration, with emphasis on recent advancements. We also discuss how a stratified approach can be undertaken for the development of future cell-based therapies to bring emerging subphenotypes into consideration.
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Affiliation(s)
- Steven Tessier
- Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, USA.,Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Iozzo RV, Theocharis AD, Neill T, Karamanos NK. Complexity of matrix phenotypes. Matrix Biol Plus 2020; 6-7:100038. [PMID: 33543032 PMCID: PMC7852209 DOI: 10.1016/j.mbplus.2020.100038] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 02/06/2023] Open
Abstract
The extracellular matrix is engaged in an ever-evolving and elegant ballet of dynamic reciprocity that directly and bi-directionally regulates cell behavior. Homeostatic and pathophysiological changes in cell-matrix signaling cascades manifest as complex matrix phenotypes. Indeed, the extracellular matrix can be implicated in virtually every known human disease, thus, making it the most critical and dynamic "organ" in the human body. The overall goal of this Special Issue is to provide an accurate and inclusive functional definition that addresses the inherent complexity of matrix phenotypes. This goal is summarily achieved via a corpus of expertly written articles, reviews and original research, focused at answering this question empirically and fundamentally via state-of-the-art methods and research strategies.
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Key Words
- ADAM, a disintegrin and metalloproteinases
- AGE, advanced glycation end products
- Angiogenesis
- Cancer
- Collagen
- DDR1, discoidin domain receptor 1
- ECM, extracellular matrix
- EGF, epidermal growth factor
- EGFR, epidermal growth factor receptor
- EMILIN1, elastin microfibril interfacer 1
- EMILIN2, elastin microfibril interfacer 2
- EMT, epithelial-mesenchymal transition
- ERα, estrogen receptor α
- ERβ, estrogen receptor β
- GBM, glioblastoma
- HA, hyaluronan
- HAS2, hyaluronan synthase 2
- HAS2-AS1, HAS2 antisense 1
- HB-EGF, heparin binding EGF
- HMGA2, high-mobility group AT-Hook 2
- IBC, inflammatory breast cancer
- IGF-IR, insulin growth factor I receptor
- IR-A, insulin receptor A
- LEKTI, lympho-epithelial Kazal-type inhibitor
- LOX, lysyl oxidases
- LTBP, latent TGFβ-binding proteins
- MAGP, microfibril-associated glycoproteins
- MET, mesenchymal-epithelial transition
- MMP, matrix metalloproteinases
- Methodologies
- OB, osteoblast
- OI, osteogenesis imperfecta
- PARs, protease activated receptors
- PG, proteoglycans
- PLL, poly-l-lysine
- Proteoglycans
- ROS, reactive oxygen species
- RTK, receptor tyrosine kinase
- SLRP, small leucine rich proteoglycans
- SSR, solar-simulated radiation
- TGFβ, transforming growth factor β
- TNT, tunneling nanotubes
- UVR, ultraviolet radiation
- VEGF, vascular endothelial growth factor
- miR, microRNA
- tPA, tissue-type plasminogen activator
- uPA, urokinase-type plasminogen activator
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Affiliation(s)
- Renato V. Iozzo
- Department of Pathology, Anatomy and Cell Biology and the Cancer Cell Biology and Signaling Program, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States of America
| | - Achilleas D. Theocharis
- Biochemistry, Biochemical Analysis and Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras, Greece
| | - Thomas Neill
- Department of Pathology, Anatomy and Cell Biology and the Cancer Cell Biology and Signaling Program, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States of America
| | - Nikos K. Karamanos
- Biochemistry, Biochemical Analysis and Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras, Greece
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Novais EJ, Tran VA, Miao J, Slaver K, Sinensky A, Dyment NA, Addya S, Szeri F, Wetering K, Shapiro IM, Risbud MV. Comparison of inbred mouse strains shows diverse phenotypic outcomes of intervertebral disc aging. Aging Cell 2020; 19:e13148. [PMID: 32319726 PMCID: PMC7253061 DOI: 10.1111/acel.13148] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 02/29/2020] [Accepted: 03/11/2020] [Indexed: 12/27/2022] Open
Abstract
Intervertebral disc degeneration presents a wide spectrum of clinically degenerative disc phenotypes; however, the contribution of genetic background to the degenerative outcomes has not been established. We characterized the spinal phenotype of 3 mouse strains with varying cartilage-regenerative potential at 6 and 23 months: C57BL/6, LG/J and SM/J. All strains showed different aging phenotypes. Importantly, LG/J mice showed an increased prevalence of dystrophic disc calcification in caudal discs with aging. Quantitative-histological analyses of LG/J and SM/J caudal discs evidenced accelerated degeneration compared to BL6, with cellular disorganization and cell loss together with fibrosis of the NP, respectively. Along with the higher grades of disc degeneration, SM/J, at 6M, also differed the most in terms of NP gene expression compared to other strains. Moreover, although we found common DEGs between BL6 and LG/J aging, most of them were divergent between the strains. Noteworthy, the common DEGs altered in both LG/J and BL6 aging were associated with inflammatory processes, response to stress, cell differentiation, cell metabolism and cell division. Results suggested that disc calcification in LG/J resulted from a dystrophic calcification process likely aggravated by cell death, matrix remodelling, changes in calcium/phosphate homeostasis and cell transformation. Lastly, we report 7 distinct phenotypes of human disc degeneration based on transcriptomic profiles, that presented similar pathways and DEGs found in aging mouse strains. Together, our results suggest that disc aging and degeneration depends on the genetic background and involves changes in various molecular pathways, which might help to explain the diverse phenotypes seen during disc disease.
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Affiliation(s)
- Emanuel J. Novais
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
- Graduate Program in Cell Biology and Regenerative Medicine Thomas Jefferson University Philadelphia PA USA
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Braga Portugal
- ICVS/3B’s – PT Government Associate Laboratory Braga Portugal
| | - Victoria A. Tran
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
| | - Jingya Miao
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
| | - Katie Slaver
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
| | - Andrew Sinensky
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
| | - Nathaniel A. Dyment
- Department of Orthopaedic Surgery University of Pennsylvania Philadelphia PA USA
| | - Sankar Addya
- Sidney Kimmel Cancer Center Thomas Jefferson University Philadelphia PA USA
| | - Flora Szeri
- Department of Dermatology and Cutaneous Biology Sidney Kimmel Medical College Thomas Jefferson University Philadelphia PA USA
- The PXE International Center of Excellence in Research and Clinical Care Thomas Jefferson University Philadelphia PA USA
- The Jefferson Institute of Molecular Medicine Thomas Jefferson University Philadelphia PA USA
| | - Koen Wetering
- Department of Dermatology and Cutaneous Biology Sidney Kimmel Medical College Thomas Jefferson University Philadelphia PA USA
- The PXE International Center of Excellence in Research and Clinical Care Thomas Jefferson University Philadelphia PA USA
- The Jefferson Institute of Molecular Medicine Thomas Jefferson University Philadelphia PA USA
| | - Irving M. Shapiro
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
- Graduate Program in Cell Biology and Regenerative Medicine Thomas Jefferson University Philadelphia PA USA
| | - Makarand V. Risbud
- Department of Orthopedic Surgery Sidney Kimmel Medical College Philadelphia PA USA
- Graduate Program in Cell Biology and Regenerative Medicine Thomas Jefferson University Philadelphia PA USA
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41
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Ohnishi T, Novais EJ, Risbud MV. Alterations in ECM signature underscore multiple sub-phenotypes of intervertebral disc degeneration. Matrix Biol Plus 2020; 6-7:100036. [PMID: 33543030 PMCID: PMC7852332 DOI: 10.1016/j.mbplus.2020.100036] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/07/2020] [Accepted: 04/07/2020] [Indexed: 12/18/2022] Open
Abstract
The intervertebral disc is a specialized connective tissue critical for absorption of mechanical loads and providing flexibility to the spinal column. The disc ECM is complex and plays a vital role in imparting tissue its biomechanical function. The central NP is primarily composed of large aggregating proteoglycans (PGs) while surrounding AF is composed of fibrillar collagens, I and II. Aggrecan and versican in particular, due to their high concentration of sulfated GAG chains form large aggregates with hyaluronic acid (HA) and provide water binding capacity to the disc. Degradation of aggrecan core protein due to aggrecanase and MMP activity, SNPs that affect number of chondroitin sulfate (CS) substitutions and alteration in enzymes critical in synthesis of CS chains can impair the aggrecan functionality. Similarly, levels of many matrix and matrix-related molecules e.g. Col2, Col9, HAS2, ccn2 are dysregulated during disc degeneration and genetic animal models have helped establish causative link between their expression and disc health. In the degenerating and herniated discs, increased levels of inflammatory cytokines such as TNF-α, IL-1β and IL-6 are shown to promote matrix degradation through regulating expression and activity of critical proteases and stimulate immune cell activation. Recent studies of different mouse strains have better elucidated the broader impact of spontaneous degeneration on disc matrix homeostasis. SM/J mice showed an increased cell apoptosis, loss of cell phenotype, and cleavage of aggrecan during early stages followed by tissue fibrosis evident by enrichment of several collagens, SLRPs and fibronectin. In summary, while disc degeneration encompasses wide spectrum of degenerative phenotypes extensive matrix degradation and remodeling underscores all of them. The intervertebral disc absorbs loads and provides flexibility to the spine. The ECM is complex and vital for imparting tissue its biomechanical function. Numerous types of proteoglycans and collagens designate the quality of the disc. Many matrix and matrix-related molecules are dysregulated during disc degeneration. Matrix degradation and remodeling underscores wide spectrum of phenotype.
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Affiliation(s)
- Takashi Ohnishi
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.,Department of Orthopaedic Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Emanuel J Novais
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.,Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga, Portugal
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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42
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Gorth DJ, Ottone OK, Shapiro IM, Risbud MV. Differential Effect of Long-Term Systemic Exposure of TNFα on Health of the Annulus Fibrosus and Nucleus Pulposus of the Intervertebral Disc. J Bone Miner Res 2020; 35:725-737. [PMID: 31800975 PMCID: PMC7145745 DOI: 10.1002/jbmr.3931] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 11/07/2019] [Accepted: 11/22/2019] [Indexed: 02/03/2023]
Abstract
The inflammatory cytokine tumor necrosis factor alpha (TNFα) is considered to play a key role in the pathogenesis of intervertebral disc disease. To evaluate the importance of this cytokine we examined the inflammatory environment and spinal phenotype of 9-month-old human TNFα overexpressing transgenic (hTNFα-TG) mice. The mice evidenced increased circulating levels of interleukin-1β (IL-1β), IL-2, keratinocyte chemoattractant/human growth-regulated oncogene (KC/GRO), and monocyte chemoattractant protein-1 (MCP-1) along with thinning of the cortical and trabecular vertebral bone. Surprisingly, although the nucleus pulposus (NP) of these mice was intact and healthy, the caudal annulus fibrosus (AF) evidenced robust cell death and immune cell infiltration. Despite these differences, there were no obvious alterations in the collagen or aggrecan content in the NP and AF. However, there was a reduction in cartilage oligomeric matrix protein (COMP), suggesting destabilization of the AF matrix. Microarray analysis of the NP from hTNFα-TG mice cells revealed minimal changes in global gene expression. These findings lend support to the notion that NP tissue is isolated from systemic inflammation. In contrast, the severe AF phenotype suggests that systemic inflammation interferes with AF health, predisposing discs to herniation as opposed to directly causing NP degeneration. © 2020 American Society for Bone and Mineral Research.
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Affiliation(s)
- Deborah J Gorth
- Department of Orthopaedic Surgery and Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Olivia K Ottone
- Department of Orthopaedic Surgery and Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Irving M Shapiro
- Department of Orthopaedic Surgery and Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery and Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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43
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Tessier S, Doolittle AC, Sao K, Rotty JD, Bear JE, Ulici V, Loeser RF, Shapiro IM, Diekman BO, Risbud MV. Arp2/3 inactivation causes intervertebral disc and cartilage degeneration with dysregulated TonEBP-mediated osmoadaptation. JCI Insight 2020; 5:131382. [PMID: 31961823 DOI: 10.1172/jci.insight.131382] [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: 06/27/2019] [Accepted: 01/15/2020] [Indexed: 01/01/2023] Open
Abstract
Extracellular matrix and osmolarity influence the development and homeostasis of skeletal tissues through Rho GTPase-mediated alteration of the actin cytoskeleton. This study investigated whether the actin-branching Arp2/3 complex, a downstream effector of the Rho GTPases Cdc42 and Rac1, plays a critical role in maintaining the health of matrix-rich and osmotically loaded intervertebral discs and cartilage. Mice with constitutive intervertebral disc- and cartilage-specific deletion of the critical Arp2/3 subunit Arpc2 (Col2-Cre; Arpc2fl/fl) developed chondrodysplasia and spinal defects. Since these mice did not survive to adulthood, we generated mice with inducible Arpc2 deletion in disc and cartilage (Acan-CreERT2; Arpc2fl/fl). Inactivation of Arp2/3 at skeletal maturity resulted in growth plate closure, loss of proteoglycan content in articular cartilage, and degenerative changes in the intervertebral disc at 1 year of age. Chondrocytes with Arpc2 deletion showed compromised cell spreading on both collagen and fibronectin. Pharmacological inhibition of Cdc42 and Arp2/3 prevented the osmoadaptive transcription factor TonEBP/NFAT5 from recruiting cofactors in response to a hyperosmolarity challenge. Together, these findings suggest that Arp2/3 plays a critical role in cartilaginous tissues through the regulation of cell-extracellular matrix interactions and modulation of TonEBP-mediated osmoadaptation.
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Affiliation(s)
- Steven Tessier
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College
| | - Alexandra C Doolittle
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College.,Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Kimheak Sao
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College.,Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Jeremy D Rotty
- Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA.,Department of Cell Biology and Physiology.,UNC Lineberger Comprehensive Cancer Center
| | - James E Bear
- Department of Cell Biology and Physiology.,UNC Lineberger Comprehensive Cancer Center
| | - Veronica Ulici
- Thurston Arthritis Research Center, and.,Division of Rheumatology, Allergy, and Immunology, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Richard F Loeser
- Thurston Arthritis Research Center, and.,Division of Rheumatology, Allergy, and Immunology, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Irving M Shapiro
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College.,Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Brian O Diekman
- Division of Rheumatology, Allergy, and Immunology, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill and Raleigh, North Carolina, USA
| | - Makarand V Risbud
- Department of Orthopaedic Surgery, Sidney Kimmel Medical College.,Graduate Program in Cell Biology and Regenerative Medicine, Jefferson College of Life Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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