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Chen X, Zhang A, Zhao K, Gao H, Shi P, Chen Y, Cheng Z, Zhou W, Zhang Y. The role of oxidative stress in intervertebral disc degeneration: Mechanisms and therapeutic implications. Ageing Res Rev 2024; 98:102323. [PMID: 38734147 DOI: 10.1016/j.arr.2024.102323] [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: 01/12/2024] [Revised: 04/19/2024] [Accepted: 05/03/2024] [Indexed: 05/13/2024]
Abstract
Oxidative stress is one of the main driving mechanisms of intervertebral disc degeneration(IDD). Oxidative stress has been associated with inflammation in the intervertebral disc, cellular senescence, autophagy, and epigenetics of intervertebral disc cells. It and the above pathological mechanisms are closely linked through the common hub reactive oxygen species(ROS), and promote each other in the process of disc degeneration and promote the development of the disease. This reveals the important role of oxidative stress in the process of IDD, and the importance and great potential of IDD therapy targeting oxidative stress. The efficacy of traditional therapy is unstable or cannot be maintained. In recent years, due to the rise of materials science, many bioactive functional materials have been applied in the treatment of IDD, and through the combination with traditional drugs, satisfactory efficacy has been achieved. At present, the research review of antioxidant bioactive materials in the treatment of IDD is not complete. Based on the existing studies, the mechanism of oxidative stress in IDD and the common antioxidant therapy were summarized in this paper, and the strategies based on emerging bioactive materials were reviewed.
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Affiliation(s)
- Xianglong Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Anran Zhang
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Kangcheng Zhao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Haiyang Gao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Pengzhi Shi
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yuhang Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Zhangrong Cheng
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Wenjuan Zhou
- Department of Operating Room, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
| | - Yukun Zhang
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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Lin CL, Su YW, Chen YW, Kuo CH, Tu TY, Tsai JC, Shyong YJ. BMSC loaded photo-crosslinked hyaluronic acid/collagen hydrogel incorporating FG4592 for enhanced cell proliferation and nucleus pulposus differentiation. Int J Biol Macromol 2024; 273:132828. [PMID: 38834125 DOI: 10.1016/j.ijbiomac.2024.132828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 05/10/2024] [Accepted: 05/30/2024] [Indexed: 06/06/2024]
Abstract
Intervertebral disc degeneration arises from damage or degeneration of the nucleus pulposus (NP). In this study, we developed a photo-crosslinkable hydrogel incorporating FG4592 to support the growth and differentiation of bone-marrow-derived mesenchymal stem cells (BMSC). Initially, hyaluronic acid was modified with tyramine and combined with collagen to introduce riboflavin as a photo-crosslinker. This hydrogel transitioned from liquid to gel upon exposure to blue light in 3 min. The results showed that the hydrogel was biodegradable and had mechanical properties comparable to those of human NP tissues. Scanning electron microscopy after BMSC seeding in the hydrogel revealed an even distribution, and cells adhered to the collagen fibers in the hydrogel with minimal cell mortality. The effect of FG4592 on BMSC proliferation and differentiation was examined, revealing the capability of FG4592 to promote BMSC proliferation and direct differentiation resembling human NP cells. After cultivating BMSCs in the photo-crosslinked hydrogel, there was an upregulation in the expression of glycosaminoglycans, aggrecan, type II collagen, and keratin 19 proteins. Cross-species analyses of rat and human BMSCs revealed consistent results. For potential clinical applications, BMSC loaded with photo-crosslinked hydrogels can be injected into damaged intervertebral disc to facilitate NP regeneration.
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Affiliation(s)
- Cheng-Li Lin
- Department of Orthopedic Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Wen Su
- School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Wei Chen
- School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Cheng-Hsiang Kuo
- International Center for Wound Repair and Regeneration, National Cheng Kung University, Tainan, Taiwan
| | - Ting-Yuan Tu
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Jui-Chen Tsai
- School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yan-Jye Shyong
- School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Eremina GM, Smolin AY. Effect of patient-specific factors on regeneration in lumbar spine at healthy disc and total disc replacement. Computer simulation. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2024; 250:108172. [PMID: 38669718 DOI: 10.1016/j.cmpb.2024.108172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/27/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024]
Abstract
BACKGROUND AND OBJECTIVE Degenerative diseases of the spine have a negative impact on the quality of life of patients. This study presents the results of numerical modelling of the mechanical behaviour of the lumbar spine with patient-specific conditions at physiological loads. This paper aims to numerically study the influence of degenerative changes in the spine and the presence of an endoprosthesis on the creation of conditions for tissue regeneration. METHODS A numerical model of the mechanical behaviour of lumbar spine at healthy and after total disc replacement under low-energy impacts equivalent to physiological loads is presented. The model is based on the movable cellular automaton method (discrete elements), where the mechanical behaviour of bone tissue is described using the Biot poroelasticity accounting for the presence and transfer of interstitial biological fluid. The nutritional pathways of the intervertebral disc in cases of healthy and osteoporotic bone tissues were predicted based on the analysis of the simulation results according to the mechanobiological principles. RESULTS Simulation of total disc replacement showed that osseointegration of the artificial disc plates occurs only in healthy bone tissue. With total disc replacement in a patient with osteoporosis, there is an area of increased risk of bone resorption in the near-contact area, approximately 1 mm wide, around the fixators. Dynamic loads may improve the osseointegration of the implant in pathological conditions of the bone tissue. CONCLUSIONS The results obtained in the case of healthy spine and osteoporotic bone tissues correspond to the experimental data on biomechanics and possible methods of IVD regeneration from the position of mechanobiological principles. The results obtained with an artificial disc (with keel-type fixation) showed that the use of this type of endoprosthesis in healthy bone tissues allows to reproduce the function of the natural intervertebral disc and does not contribute to the development of neoplastic processes. In the case of an artificial disc with osteoporosis of bone tissues, there is a zone with increased risk of tissue resorption and development of neoplastic processes in the area near the contact of the implant attachment. This circumstance can be compensated by increasing the loading level.
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Affiliation(s)
- Galina M Eremina
- Institute of Strength Physics and Materials Science of SB RAS, 2/4, pr. Akademicheskii, Tomsk, 634055, Russia.
| | - Alexey Yu Smolin
- Institute of Strength Physics and Materials Science of SB RAS, 2/4, pr. Akademicheskii, Tomsk, 634055, Russia
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Naresh-Babu J, Gajendra, Prajwal GS. ISSLS prize in clinical/bioengineering science 2024: How standing and supine positions influence nutrient transport in human lumbar discs?-A serial post-contrast MRI study evaluating interplay between convection and diffusion. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2024; 33:1728-1736. [PMID: 38662214 DOI: 10.1007/s00586-024-08243-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 03/27/2024] [Accepted: 03/31/2024] [Indexed: 04/26/2024]
Abstract
PURPOSE The intervertebral disc being avascular depends on diffusion and load-based convection for essential nutrient supply and waste removal. There are no reliable methods to simultaneously investigate them in humans under natural loads. For the first time, present study aims to investigate this by strategically employing positional MRI and post-contrast studies in three physiological positions: supine, standing and post-standing recovery. METHODS A total of 100 healthy intervertebral discs from 20 volunteers were subjected to a serial post-contrast MR study after injecting 0.3 mmol/kg gadodiamide and T1-weighted MR images were obtained at 0, 2, 6, 12 and 24 h. At each time interval, images were obtained in three positions, i.e. supine, standing and post-standing recovery supine. The signal intensity values at endplate zone and nucleus pulposus were measured. Enhancement percentages were calculated and analysed comparing three positions. RESULTS During unloaded supine position, there was slow gradual increase in enhancement reaching peak at 6 h. When the subjects assumed standing position, there was immediate loss of enhancement at nucleus pulposus which resulted in reciprocal increase in enhancement at endplate zone (washout phenomenon). Interestingly, when subjects assumed the post-standing recovery position, the nucleus pulposus regained the enhancement and endplate zone showed reciprocal loss (pumping-in phenomenon). CONCLUSIONS For the first time, present study documented acute effects of physiological loading and unloading on nutrition of human discs in vivo. While during rest, solutes diffused gradually into disc, the diurnal short loading and unloading redistribute small solutes by convection. Standing caused rapid solute depletion but promptly regained by assuming resting supine position.
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Affiliation(s)
- J Naresh-Babu
- Director and Chief Spine Surgeon, Mallika Spine Centre, Guntur, AP, India.
| | - Gajendra
- Fellow in Spine Surgery, Mallika Spine Centre, Guntur, AP, India
| | - G S Prajwal
- Fellow in Spine Surgery, Mallika Spine Centre, Guntur, AP, India
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Song C, Hu P, Peng R, Li F, Fang Z, Xu Y. Bioenergetic dysfunction in the pathogenesis of intervertebral disc degeneration. Pharmacol Res 2024; 202:107119. [PMID: 38417775 DOI: 10.1016/j.phrs.2024.107119] [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: 01/04/2024] [Revised: 02/16/2024] [Accepted: 02/24/2024] [Indexed: 03/01/2024]
Abstract
Intervertebral disc (IVD) degeneration is a frequent cause of low back pain and is the most common cause of disability. Treatments for symptomatic IVD degeneration, including conservative treatments such as analgesics, physical therapy, anti-inflammatories and surgeries, are aimed at alleviating neurological symptoms. However, there are no effective treatments to prevent or delay IVD degeneration. Previous studies have identified risk factors for IVD degeneration such as aging, inflammation, genetic factors, mechanical overload, nutrient deprivation and smoking, but metabolic dysfunction has not been highlighted. IVDs are the largest avascular structures in the human body and determine the hypoxic and glycolytic features of nucleus pulposus (NP) cells. Accumulating evidence has demonstrated that intracellular metabolic dysfunction is associated with IVD degeneration, but a comprehensive review is lacking. Here, by reviewing the physiological features of IVDs, pathological processes and metabolic changes associated with IVD degeneration and the functions of metabolic genes in IVDs, we highlight that glycolytic pathway and intact mitochondrial function are essential for IVD homeostasis. In degenerated NPs, glycolysis and mitochondrial function are downregulated. Boosting glycolysis such as HIF1α overexpression protects against IVD degeneration. Moreover, the correlations between metabolic diseases such as diabetes, obesity and IVD degeneration and their underlying molecular mechanisms are discussed. Hyperglycemia in diabetic diseases leads to cell senescence, the senescence-associated phenotype (SASP), apoptosis and catabolism of extracellualr matrix in IVDs. Correcting the global metabolic disorders such as insulin or GLP-1 receptor agonist administration is beneficial for diabetes associated IVD degeneration. Overall, we summarized the recent progress of investigations on metabolic contributions to IVD degeneration and provide a new perspective that correcting metabolic dysfunction may be beneficial for treating IVD degeneration.
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Affiliation(s)
- Chao Song
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Peixuan Hu
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Renpeng Peng
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Feng Li
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China.
| | - Zhong Fang
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China.
| | - Yong Xu
- Department of Orthopaedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China.
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Tanoren B, Dipcin B, Birdogan S, Unlu MB, Ozdol C, Aghayev K. Examination of annulus fibrosus and nucleus pulposus in cervical and lumbar intervertebral disc herniation patients by scanning acoustic microscopy, scanning electron microscopy and energy dispersive spectroscopy. RSC Adv 2024; 14:2603-2609. [PMID: 38226141 PMCID: PMC10788776 DOI: 10.1039/d3ra07195b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 12/18/2023] [Indexed: 01/17/2024] Open
Abstract
Intervertebral disc herniation (IVDH) is observed in humans as a result of the alteration of annulus fibrous (AF) and nucleus pulposus (NP) tissue compositions in intervertebral discs. In this study, we studied the feasibility of scanning acoustic microscopy (SAM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) in characterizing the herniated segments of AF and NP tissues from male and female patients. SAM determined the acoustic property variations in AF and NP tissues by calculating the acoustic impedance values of samples of 15 patients. SEM obtained higher resolution images and EDS made elemental analysis of the specimen. Consequently, we suggest that these techniques have the potential to be combined for the investigation and removal of the disrupted AF and NP tissues with micrometer resolution in clinics.
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Affiliation(s)
- Bukem Tanoren
- Acibadem University, Faculty of Engineering and Natural Sciences, Department of Natural Sciences Istanbul Turkey +90 216 500 4156 +90 216 576 5076
| | - Beste Dipcin
- Acibadem University, Faculty of Engineering and Natural Sciences, Department of Molecular Biology and Genetics Istanbul Turkey
| | - Selcuk Birdogan
- Sabanci University SUNUM Nanotechnology Research and Application Center Istanbul Turkey
| | | | - Cagatay Ozdol
- Antalya Education and Research Hospital Istanbul Turkey
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Kim Y, An SB, Lee SH, Lee JJ, Kim SB, Ahn JC, Hwang DY, Han I. Enhanced Intervertebral Disc Repair via Genetically Engineered Mesenchymal Stem Cells with Tetracycline Regulatory System. Int J Mol Sci 2023; 24:16024. [PMID: 38003216 PMCID: PMC10671788 DOI: 10.3390/ijms242216024] [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: 09/30/2023] [Revised: 10/28/2023] [Accepted: 11/01/2023] [Indexed: 11/26/2023] Open
Abstract
The therapeutic potential of Mesenchymal stem cells (MSCs) for the treatment of Intervertebral disc (IVD) degeneration can be enhanced by amplifying specific cytokines and proteins. This study aimed to investigate the therapeutic potential of tetracycline-off system-engineered tonsil-derived mesenchymal stem cells (ToMSC-Tetoff-TGFβ1-IGF1-BMP7) for treating intervertebral disc (IVD) degeneration. ToMSCs were isolated from a tonsillectomy patient and genetically modified with four distinct plasmids via CRISPR/Cas9-mediated knock-in gene editing. Transgene expression was confirmed through immunofluorescence, western blots, and an enzyme-linked immunosorbent assay for transforming growth factor beta 1 (TGFβ1) protein secretion, and the effect of MSC-TetOff-TGFβ1-IGF1-BMP7 on disc injury was assessed in a rat model. The ToMSC-Tetoff-TGFβ1-IGF1-BMP7 treatment exhibited superior therapeutic effects compared to ToMSC-TGFβ1, and ToMSC-SDF1α implantation groups, stimulating the regeneration of nucleus pulposus (NP) cells crucial for IVD. The treatment showed potential to restore the structural integrity of the extracellular matrix (ECM) by upregulating key molecules such as aggrecan and type II collagen. It also exhibited anti-inflammatory properties and reduced pain-inducing neuropeptides. ToMSC-Tetoff-TGFβ1-IGF1-BMP7 holds promise as a novel treatment for IVD degeneration. It appears to promote NP cell regeneration, restore ECM structure, suppress inflammation, and reduce pain. However, more research and clinical trials are required to confirm its therapeutic potential.
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Affiliation(s)
- Yeji Kim
- Research Competency Milestones Program of School of Medicine, CHA University School of Medicine, Seongnam-si 13496, Republic of Korea;
| | - Seong Bae An
- Department of Biomedical Science, Graduate School of CHA University, Seongnam-si 13496, Republic of Korea;
| | - Sang-Hyuk Lee
- Department of Neurosurgery, CHA University School of Medicine, CHA Bundang Medical Center, Seongnam-si 13496, Republic of Korea;
| | - Jong Joo Lee
- Department of Medicine, Graduate School, Kyung Hee University, Seoul 02453, Republic of Korea;
- Department of Neurosurgery, Kangbuk Samsung Hospital, Sungkyunkwan University College of Medicine, Seoul 03181, Republic of Korea
| | - Sung Bum Kim
- Department of Neurosurgery, Kyung Hee University, Seoul 02453, Republic of Korea;
| | - Jae-Cheul Ahn
- Department of Otorhinolaryngology-Head and Neck Surgery, CHA University School of Medicine, CHA Bundang Medical Center, Seongnam-si 13496, Republic of Korea
| | - Dong-Youn Hwang
- Department of Neurosurgery, CHA University School of Medicine, CHA Bundang Medical Center, Seongnam-si 13496, Republic of Korea;
- Department of Microbiology, School of Medicine, CHA University, Seongnam-si 13496, Republic of Korea
| | - Inbo Han
- Department of Biomedical Science, Graduate School of CHA University, Seongnam-si 13496, Republic of Korea;
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Fotakopoulos G, Georgakopoulou VE, Lempesis IG, Papalexis P, Sklapani P, Trakas N, Spandidos DA, Faropoulos K. Pathophysiology of cervical myelopathy (Review). Biomed Rep 2023; 19:84. [PMID: 37881604 PMCID: PMC10594073 DOI: 10.3892/br.2023.1666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/18/2023] [Indexed: 10/27/2023] Open
Abstract
Cervical myelopathy is a well-described medulla spinalis syndrome characterized by sensory disorders, such as pain, numbness, or paresthesia in the limbs, and motor disorders, such as muscle weakness, gait difficulties, spasticity, or hyperreflexia. If left untreated, cervical myelopathy can significantly affect the quality of life of patients, while in severe cases, it can cause disability or even quadriplegia. Cervical myelopathy is the final stage of spinal cord insult and can result from transgene dysplasias of the spinal cord, and acute or chronic injuries. Spondylosis is a common, multifactor cause of cervical myelopathy and affects various elements of the spine. The development of spondylotic changes in the spine is gradual during the patient's life and the symptoms are presented at a late stage, when significant damage has already been inflicted on the spinal cord. Spondylosis is widely considered a condition affecting the middle aged and elderly. Given the fact that the population is gradually becoming older, in the near future, clinicians may have to face an increased number of patients with spondylotic myelopathy.
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Affiliation(s)
- George Fotakopoulos
- Department of Neurosurgery, General University Hospital of Larissa, 41221 Larissa, Greece
| | | | - Ioannis G. Lempesis
- Department of Pathophysiology, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Petros Papalexis
- Unit of Endocrinology, First Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
- Department of Biomedical Sciences, University of West Attica, 12243 Athens, Greece
| | - Pagona Sklapani
- Department of Biochemistry, Sismanogleio Hospital, 15126 Athens, Greece
| | - Nikolaos Trakas
- Department of Biochemistry, Sismanogleio Hospital, 15126 Athens, Greece
| | - Demetrios A. Spandidos
- Laboratory of Clinical Virology, School of Medicine, University of Crete, 71003 Heraklion, Greece
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9
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Pang H, Chen S, Klyne DM, Harrich D, Ding W, Yang S, Han FY. Low back pain and osteoarthritis pain: a perspective of estrogen. Bone Res 2023; 11:42. [PMID: 37542028 PMCID: PMC10403578 DOI: 10.1038/s41413-023-00280-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 06/28/2023] [Accepted: 07/10/2023] [Indexed: 08/06/2023] Open
Abstract
Low back pain (LBP) is the world's leading cause of disability and is increasing in prevalence more rapidly than any other pain condition. Intervertebral disc (IVD) degeneration and facet joint osteoarthritis (FJOA) are two common causes of LBP, and both occur more frequently in elderly women than in other populations. Moreover, osteoarthritis (OA) and OA pain, regardless of the joint, are experienced by up to twice as many women as men, and this difference is amplified during menopause. Changes in estrogen may be an important contributor to these pain states. Receptors for estrogen have been found within IVD tissue and nearby joints, highlighting the potential roles of estrogen within and surrounding the IVDs and joints. In addition, estrogen supplementation has been shown to be effective at ameliorating IVD degeneration and OA progression, indicating its potential use as a therapeutic agent for people with LBP and OA pain. This review comprehensively examines the relationship between estrogen and these pain conditions by summarizing recent preclinical and clinical findings. The potential molecular mechanisms by which estrogen may relieve LBP associated with IVD degeneration and FJOA and OA pain are discussed.
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Affiliation(s)
- Huiwen Pang
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Shihui Chen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - David M Klyne
- NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - David Harrich
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, QLD, 4006, Australia
| | - Wenyuan Ding
- Department of Spine Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, China
- Hebei Joint International Research Center for Spinal Diseases, 139 Ziqiang Road, Shijiazhuang, 050051, China
| | - Sidong Yang
- Department of Spine Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, Shijiazhuang, 050051, China.
- Hebei Joint International Research Center for Spinal Diseases, 139 Ziqiang Road, Shijiazhuang, 050051, China.
| | - Felicity Y Han
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia.
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10
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Huang CY, Loo DM, Gu W. Modeling of glycosaminoglycan biosynthesis in intervertebral disc cells. Comput Biol Med 2023; 162:107039. [PMID: 37295387 DOI: 10.1016/j.compbiomed.2023.107039] [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: 10/05/2022] [Revised: 05/05/2023] [Accepted: 05/12/2023] [Indexed: 06/12/2023]
Abstract
Loss of proteoglycan (PG) is a potential factor responsible for degeneration of the intervertebral disc (IVD). PG consists of a core protein with covalently attached glycosaminoglycan (GAG) chains. The objective of this study was to develop a mathematical model of GAG biosynthesis to investigate the effects of glycolytic enzymes on GAG biosynthesis of IVD cells. A new mathematical model of GAG biosynthesis was developed for IVD cells by incorporating biosynthesis of uridine diphosphate-sugars into the glycolytic pathway. This new model showed good agreement between the model predictions of intracellular ATP content and GAG biosynthesis and experimental data measured at different external glucose levels. The quantitative analyses demonstrated that GAG biosynthesis may be sensitive to the activities of hexokinase (HK) and phosphofructokinase (PFK), especially at low glucose supply, with GAG biosynthesis being significantly enhanced by a slight increase in activities of HK and PFK. This suggests that metabolic reprogramming could be a potential strategy for promoting PG biosynthesis in IVD cells. Furthermore, it was shown that GAG biosynthesis may be promoted by increasing intracellular glutamine concentration or activity of glutamine:fructose-6-phosphate amidotransferase in the hexamine pathway. This study provides a better understanding of the relationship between glycolysis and PG biosynthesis in IVD cells. The theoretical framework developed in this study is useful for studying the role of glycolysis in disc degeneration and developing new preventive and treatment strategies for degeneration of the IVD.
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Affiliation(s)
- Chun-Yuh Huang
- Department of Biomedical Engineering, University of Miami, Coral Gables, FL, USA.
| | - Daniela M Loo
- Department of Biomedical Engineering, University of Miami, Coral Gables, FL, USA
| | - Weiyong Gu
- Department of Mechanical and Aerospace Engineering, University of Miami, Coral Gables, FL, USA
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Li X, Liu Y, Li L, Huo R, Ghezelbash F, Ma Z, Bao G, Liu S, Yang Z, Weber MH, Li-Jessen NYK, Haglund L, Li J. Tissue-mimetic hybrid bioadhesives for intervertebral disc repair. MATERIALS HORIZONS 2023; 10:1705-1718. [PMID: 36857679 DOI: 10.1039/d2mh01242a] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Intervertebral disc (IVD) degeneration and herniation often necessitate surgical interventions including a discectomy with or without a nucleotomy, which results in a loss of the normal nucleus pulposus (NP) and a defect in the annulus fibrosus (AF). Due to the limited regenerative capacity of the IVD tissue, the annular tear may remain a persistent defect and result in recurrent herniation post-surgery. Bioadhesives are promising alternatives but show limited adhesion performance, low regenerative capacity, and inability to prevent re-herniation. Here, we report hybrid bioadhesives that combine an injectable glue and a tough sealant to simultaneously repair and regenerate IVD post-nucleotomy. The glue fills the NP cavity while the sealant seals the AF defect. Strong adhesion occurs with the IVD tissues and survives extreme disc loading. Furthermore, the glue can match native NP mechanically, and support the viability and matrix deposition of encapsulated cells, serving as a suitable cell delivery vehicle to promote NP regeneration. Besides, biomechanical tests with bovine IVD motion segments demonstrate the capacity of the hybrid bioadhesives to restore the biomechanics of bovine discs under cyclic loading and to prevent permanent herniation under extreme loading. This work highlights the synergy of bioadhesive and tissue-engineering approaches. Future works are expected to further improve the tissue specificity of bioadhesives and prove their efficacy for tissue repair and regeneration.
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Affiliation(s)
- Xuan Li
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Yin Liu
- Department of Biomedical Engineering, McGill University, 3775 rue University, Montreal, Quebec H3A 2B4, Canada
| | - Li Li
- Department of Surgery, McGill University, 1650 Cedar Avenue, Room C10.148.2, Montreal, QC, H3G 1A4, Canada.
| | - Ran Huo
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Farshid Ghezelbash
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
- Department of Mechanical Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada
| | - Zhenwei Ma
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Guangyu Bao
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Shiyu Liu
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Zhen Yang
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
| | - Michael H Weber
- Department of Surgery, McGill University, 1650 Cedar Avenue, Room C10.148.2, Montreal, QC, H3G 1A4, Canada.
| | - Nicole Y K Li-Jessen
- Department of Biomedical Engineering, McGill University, 3775 rue University, Montreal, Quebec H3A 2B4, Canada
- School of Communication Sciences and Disorders, McGill University, Montreal, Quebec H3A 1G1, Canada
- Department of Otolaryngology-Head & Neck Surgery, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Lisbet Haglund
- Department of Surgery, McGill University, 1650 Cedar Avenue, Room C10.148.2, Montreal, QC, H3G 1A4, Canada.
| | - Jianyu Li
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke St W, Montreal, QC H3A 0C3, Canada.
- Department of Biomedical Engineering, McGill University, 3775 rue University, Montreal, Quebec H3A 2B4, Canada
- Department of Surgery, McGill University, 1650 Cedar Avenue, Room C10.148.2, Montreal, QC, H3G 1A4, Canada.
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12
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Khalid S, Ekram S, Ramzan F, Salim A, Khan I. Co-regulation of Sox9 and TGFβ1 transcription factors in mesenchymal stem cells regenerated the intervertebral disc degeneration. Front Med (Lausanne) 2023; 10:1127303. [PMID: 37007782 PMCID: PMC10063891 DOI: 10.3389/fmed.2023.1127303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 02/20/2023] [Indexed: 03/19/2023] Open
Abstract
BackgroundIntervertebral disc (IVD) shows aging and degenerative changes earlier than any other body connective tissue. Its repair and regeneration provide a considerable challenge in regenerative medicine due to its high degree of infrastructure and mechanical complexity. Mesenchymal stem cells, due to their tissue resurfacing potential, represent many explanatory pathways to regenerate a tissue breakdown.MethodsThis study was undertaken to evaluate the co-regulation of Sox9 and TGFβ1 in differentiating human umbilical cord mesenchymal stem cells (hUC-MSC) into chondrocytes. The combinatorial impact of Sox9 and TGFβ1 on hUC-MSCs was examined in vitro by gene expression and immunocytochemical staining. In in vivo, an animal model of IVD degeneration was established under a fluoroscopic guided system through needle puncture of the caudal disc. Normal and transfected MSCs were transplanted. Oxidative stress, pain, and inflammatory markers were evaluated by qPCR. Disc height index (DHI), water content, and gag content were analyzed. Histological examinations were performed to evaluate the degree of regeneration.ResultshUC-MSC transfected with Sox9+TGFβ1 showed a noticeable morphological appearance of a chondrocyte, and highly expressed chondrogenic markers (aggrecan, Sox9, TGFβ1, TGFβ2, and type II collagens) after transfection. Histological observation demonstrated that cartilage regeneration, extracellular matrix synthesis, and collagen remodeling were significant upon staining with H&E, Alcian blue, and Masson's trichrome stain on day 14. Additionally, oxidative stress, pain, and inflammatory markers were positively downregulated in the animals transplanted with Sox9 and TGFβ1 transfected MSCs.ConclusionThese findings indicate that the combinatorial effect of Sox9 and TGFβ1 substantially accelerates the chondrogenesis in hUC-MSCs. Cartilage regeneration and matrix synthesis were significantly enhanced. Therefore, a synergistic effect of Sox9 and TGFβ1 could be an immense therapeutic combination in the tissue engineering of cartilaginous joint bio-prostheses and a novel candidate for cartilage stabilization.
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13
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Bari E, Perteghella S, Rassu G, Gavini E, Petretto GL, Bonferoni MC, Giunchedi P, Torre ML. Sericin/crocetin micro/nanoparticles for nucleus pulposus cells regeneration: An “active” drug delivery system. Front Pharmacol 2023; 14:1129882. [PMID: 36969863 PMCID: PMC10036567 DOI: 10.3389/fphar.2023.1129882] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/01/2023] [Indexed: 03/12/2023] Open
Abstract
Introduction: Initiation and progression of intervertebral disk degeneration are linked to oxidative stress, with reactive oxygen species being a key factor. Therefore, as a potentially novel approach able to regenerate the damaged intervertebral disk, this work aimed to prepare an “active per sé” drug delivery system by combining sericin and crocetin: both are bioactive compounds with antioxidant, anti-inflammatory, immunomodulant and regenerative properties.Methods: In detail, sericin nanoparticles were prepared using crocetin as a cross-linker; then, the nanoparticle dispersions were dried by spray drying as it is (NP), with an excess of sericin (NPS) or crocin/crocetin (NPMix), obtaining three microparticle formulations.Results and Discussion: Before drying, the nanoparticles were nanometric (about 250 nm), with a negative surface charge, and appeared spherical and smooth. Following the drying process, spherical and smooth microparticles were obtained, with a mean diameter of about 1.7–2.30 μm. NPMix was the most active in antioxidant and anti-tyrosinase activities, likely due to the excess of crocin/crocetin, while NPS had the best anti-elastase activity, likely due to sericin in excess. Furthermore, all the formulations could prevent oxidative stress damage on nucleus pulposus cells, with NPMix being the best. Overall, the intrinsic anti-tyrosinase and anti-elastase activities and the ability to protect from oxidative stress-induced damages justify future investigations of these “active per sé” formulations in treating or preventing intervertebral disk degeneration.
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Affiliation(s)
- Elia Bari
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Novara, Italy
| | | | - Giovanna Rassu
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Sassari, Italy
- *Correspondence: Giovanna Rassu,
| | - Elisabetta Gavini
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Sassari, Italy
| | | | | | - Paolo Giunchedi
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Sassari, Italy
| | - Maria Luisa Torre
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Novara, Italy
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14
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Lillyman DJ, Barnett EC, Miller TJ, Wachs RA. Application of microcomputed tomography to calculate rat intervertebral disc volume as a surrogate measure of degeneration. COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING: IMAGING & VISUALIZATION 2023. [DOI: 10.1080/21681163.2023.2182607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Affiliation(s)
- David J. Lillyman
- Department of Biological Systems Engineering, University of Nebraska, Lincoln, Nebraska, USA
| | - Evie C. Barnett
- Department of Biological Systems Engineering, University of Nebraska, Lincoln, Nebraska, USA
| | - Tyler J. Miller
- Department of Biological Systems Engineering, University of Nebraska, Lincoln, Nebraska, USA
| | - Rebecca A. Wachs
- Department of Biological Systems Engineering, University of Nebraska, Lincoln, Nebraska, USA
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15
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Akkarakittichoke N, Waongenngarm P, Janwantanakul P. Effects of Postural Shifting Frequency on Perceived Musculoskeletal Discomfort During 1-Hour Sitting in Office Workers. J Manipulative Physiol Ther 2023; 46:76-85. [PMID: 37777939 DOI: 10.1016/j.jmpt.2023.06.003] [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: 11/11/2022] [Revised: 05/22/2023] [Accepted: 06/26/2023] [Indexed: 10/02/2023]
Abstract
OBJECTIVE The purpose of this study was to evaluate the effects of postural shifting frequency on perceived musculoskeletal discomfort during 1 hour of sitting in healthy office workers. METHODS An experimental study comparing 3 different postural shifting frequencies was conducted on 60 healthy office workers who were asked to sit for an hour. The effects of 3 postural shifts (ie, 10, 20, and 30 times/h) on discomfort, measured by Borg's CR-10 scale, were compared. A seat pressure mat was used to confirm an individual's postural shift. RESULTS Postural shifting frequency of 10 to 30 times/h had significant effects on perceived discomfort in the neck, shoulder, and upper and lower back during 1-hour sitting. At the neck and shoulder, a postural shifting frequency of 30 times/h significantly reduced perceived discomfort compared to a postural shifting frequency of 10 times/h during 1-hour sitting. At the upper and lower back, a postural shifting frequency of 20 to 30 times/h significantly reduced perceived discomfort compared to a postural shifting frequency of 10 times/h. CONCLUSION Postural shifts of 30 times/h provided buffering effects on perceived musculoskeletal discomfort at the neck, shoulder, and upper and lower back.
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Affiliation(s)
- Nipaporn Akkarakittichoke
- Department of Physical Therapy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Pooriput Waongenngarm
- Faculty of Health Science Technology, HRH Princess Chulabhorn College of Medical Science, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Prawit Janwantanakul
- Department of Physical Therapy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand.
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16
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Mu J, Liu Z, Chen S, Niu H, Zhang G, Lian X. Intervertebral Disk Regeneration in a Rat Model via a Nanocomposite Collagen Hydrogel Loaded with Galanthus Extract: An In Vitro and In Vivo Study. J Biomed Nanotechnol 2022. [DOI: 10.1166/jbn.2022.3483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
In the current study, Galanthus extract was loaded into electrospun gelatin scaffolds using an electrospun method and then crushed. The resulting nanofibers were loaded into a collagen hydrogel to develop a filler material to treat nucleus pulposus injuries in the intervertebral
disks. The nanocomposite hydrogel was studied regarding its biocompatibility, antiinflammatory activity, and swelling behavior. In Vivo study was performed in a rat model of intervertebral disk injury. Histopathological studies showed that the animals treated with the nanocomposite
hydrogel restored its nucleus pulposus to a significantly higher extent than other experimental groups.
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17
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Diwan AD, Melrose J. Intervertebral disc degeneration and how it leads to low back pain. JOR Spine 2022; 6:e1231. [PMID: 36994466 PMCID: PMC10041390 DOI: 10.1002/jsp2.1231] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 09/23/2022] [Accepted: 10/21/2022] [Indexed: 11/16/2022] Open
Abstract
The purpose of this review was to evaluate data generated by animal models of intervertebral disc (IVD) degeneration published in the last decade and show how this has made invaluable contributions to the identification of molecular events occurring in and contributing to pain generation. IVD degeneration and associated spinal pain is a complex multifactorial process, its complexity poses difficulties in the selection of the most appropriate therapeutic target to focus on of many potential candidates in the formulation of strategies to alleviate pain perception and to effect disc repair and regeneration and the prevention of associated neuropathic and nociceptive pain. Nerve ingrowth and increased numbers of nociceptors and mechanoreceptors in the degenerate IVD are mechanically stimulated in the biomechanically incompetent abnormally loaded degenerate IVD leading to increased generation of low back pain. Maintenance of a healthy IVD is, thus, an important preventative measure that warrants further investigation to preclude the generation of low back pain. Recent studies with growth and differentiation factor 6 in IVD puncture and multi-level IVD degeneration models and a rat xenograft radiculopathy pain model have shown it has considerable potential in the prevention of further deterioration in degenerate IVDs, has regenerative properties that promote recovery of normal IVD architectural functional organization and inhibits the generation of inflammatory mediators that lead to disc degeneration and the generation of low back pain. Human clinical trials are warranted and eagerly anticipated with this compound to assess its efficacy in the treatment of IVD degeneration and the prevention of the generation of low back pain.
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Affiliation(s)
- Ashish D. Diwan
- Spine Service, Department of Orthopaedic Surgery, St. George & Sutherland Clinical School University of New South Wales Sydney New South Wales Australia
| | - James Melrose
- Raymond Purves Bone and Joint Research Laboratory Kolling Institute, Sydney University Faculty of Medicine and Health, Northern Sydney Area Health District, Royal North Shore Hospital Sydney New South Wales Australia
- Graduate School of Biomedical Engineering The University of New South Wales Sydney New South Wales Australia
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18
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Integrative Bioinformatics Analysis Revealed Mitochondrial Dysfunction-Related Genes Underlying Intervertebral Disc Degeneration. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:1372483. [PMID: 36267810 PMCID: PMC9578809 DOI: 10.1155/2022/1372483] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/15/2022] [Indexed: 11/25/2022]
Abstract
Objective Mitochondrial dysfunction plays an important role in intervertebral disc degeneration (IDD). We aim to explore the pathways and key genes that cause mitochondrial dysfunction during IDD and to further reveal the pathogenesis of IDD based on bioinformatic analyses. Methods Datasets GSE70362 and GSE124272 were downloaded from the Gene Expression Omnibus. Differentially expressed genes (DEGs) of mitochondrial dysfunction between IDD patients and healthy controls were screened by package limma package. Critical genes were identified by adopting gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG) pathways, and protein-protein interaction (PPI) networks. We collected both degenerated and normal disc tissues obtained surgically, and we performed western blot and qPCR to verify the key DEGs identified in intervertebral disc tissues. Results In total, 40 cases of IDD and 24 healthy controls were included. We identified 152 DEGs, including 67 upregulated genes and 85 downregulated genes. Four genes related to mitochondrial dysfunction (SOX9, FLVCR1, NR5A1 and UCHL1) were screened out. Of them, SOX9, FLVCR1, and UCHL1 were down-regulated in peripheral blood and intervertebral disc tissues of IDD patients, while NR5A1 was up-regulated. The analysis of immune infiltration showed the concentrations of mast cells activated were significantly the highest in IDD patients. Compared with the control group, the level of T cells CD4 memory resting was the lowest in the patients. In addition, 24 cases of IDD tissues and 12 cases of normal disc tissues were obtained to verify the results of bioinformatics analysis. Both western blot and qPCR results were consistent with the results of bioinformatics analysis. Conclusion We identified four genes (SOX9, FLVCR1, NR5A1 and UCHL1) associated with mitochondrial dysfunction that play an important role in the progress of disc degeneration. The identification of these differential genes may provide new insights for the diagnosis and treatment of IDD.
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19
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McKinley JP, Montes AR, Wang MN, Kamath AR, Jimenez G, Lim J, Marathe SA, Mofrad MRK, O’Connell GD. Design of a flexing organ-chip to model in situ loading of the intervertebral disc. BIOMICROFLUIDICS 2022; 16:054111. [PMID: 36330201 PMCID: PMC9625834 DOI: 10.1063/5.0103141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
The leading cause of disability of all ages worldwide is severe lower back pain. To address this untreated epidemic, further investigation is needed into the leading cause of back pain, intervertebral disc degeneration. In particular, microphysiological systems modeling critical tissues in a degenerative disc, like the annulus fibrosus (AF), are needed to investigate the effects of complex multiaxial strains on AF cells. By replicating these mechanobiological effects unique to the AF that are not yet understood, we can advance therapies for early-stage degeneration at the cellular level. To this end, we designed, fabricated, and collected proof-of-concept data for a novel microphysiological device called the flexing annulus-on-a-chip (AoC). We used computational models and experimental measurements to characterize the device's ability to mimic complex physiologically relevant strains. As a result, these strains proved to be controllable, multi-directional, and uniformly distributed with magnitudes ranging from - 10 % to 12% in the axial, radial, and circumferential directions, which differ greatly from applied strains possible in uniaxial devices. Furthermore, after withstanding accelerated life testing (66 K cycles of 10% strain) and maintaining 2000 bovine AF cells without loading for more than three weeks the AoC proved capable of long-term cell culture. Additionally, after strain (3.5% strain for 75 cycles at 0.5 Hz) was applied to a monolayer of AF cells in the AoC, a population remained adhered to the channel with spread morphology. The AoC can also be tailored for other annular structures in the body such as cardiovascular vessels, lymphatic vessels, and the cervix.
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Affiliation(s)
- Jonathan P. McKinley
- Department of Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Andre R. Montes
- Department of Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Maple N. Wang
- Department of Bioengineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Anuya R. Kamath
- Department of Bioengineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Gissell Jimenez
- Department of Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Jianhua Lim
- Department of Bioengineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Siddharth A. Marathe
- Department of Bioengineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Mohammad R. K. Mofrad
- Department of Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Grace D. O’Connell
- Department of Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
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20
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Lillyman DJ, Lee FS, Barnett EC, Miller TJ, Alvaro ML, Drvol HC, Wachs RA. Axial hypersensitivity is associated with aberrant nerve sprouting in a novel model of disc degeneration in female Sprague Dawley rats. JOR Spine 2022; 5:e1212. [PMID: 36203864 PMCID: PMC9520768 DOI: 10.1002/jsp2.1212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/26/2022] [Accepted: 06/07/2022] [Indexed: 11/30/2022] Open
Abstract
Chronic low back pain is a global socioeconomic crisis and treatments are lacking in part due to inadequate models. Etiological research suggests that the predominant pathology associated with chronic low back pain is intervertebral disc degeneration. Various research teams have created rat models of disc degeneration, but the clinical translatability of these models has been limited by an absence of robust chronic pain‐like behavior. To address this deficit, disc degeneration was induced via an artificial annular tear in female Sprague Dawley rats. The subsequent degeneration, which was allowed to progress for 18‐weeks, caused a drastic reduction in disc volume. Furthermore, from week 10 till study conclusion, injured animals exhibited significant axial hypersensitivity. At study end, intervertebral discs were assessed for important characteristics of human degenerated discs: extracellular matrix breakdown, hypocellularity, inflammation, and nerve sprouting. All these aspects were significantly increased in injured animals compared to sham controls. Also of note, 20 significant correlations were detected between selected outcomes including a moderate and highly significant correlation (R = 0.59, p < 0.0004) between axial hypersensitivity and disc nerve sprouting. These data support this model as a rigorous platform to explore the pathobiology of disc‐associated low back pain and to screen treatments.
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Affiliation(s)
- David J. Lillyman
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Fei San Lee
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Evie C. Barnett
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Tyler J. Miller
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Moreno Lozano Alvaro
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Henry C. Drvol
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
| | - Rebecca A. Wachs
- Department of Biological Systems Engineering University of Nebraska Lincoln Nebraska USA
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21
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In-vitro models of disc degeneration - A review of methods and clinical relevance. J Biomech 2022; 142:111260. [PMID: 36027637 DOI: 10.1016/j.jbiomech.2022.111260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 07/22/2022] [Accepted: 08/11/2022] [Indexed: 11/21/2022]
Abstract
The intervertebral disc (IVD) provides flexibility, acts as a shock absorber, and transmits load. Degeneration of the IVD includes alterations in the biomechanics, extracellular matrix (ECM), and cellular activity. These changes are not always perceived, however, IVD degeneration can lead to severe health problems including long-term disability. To understand the pathogenesis of IVD degeneration and suitable testing methods for emerging treatments and therapies, this review documents in-vitro models of IVD degeneration including physical disruption, hyperphysiological loading, ECM degradation by enzyme digestion, or a combination of these methods. This paper reviews and critically analyses the models of degeneration published since the year 2000 in either in human or animal specimens. The results are categorised in terms of the IVD biomechanics, physical attributes, ECM composition, tissue damage and cellularity to evaluate the models with respect to natural human degeneration, and to provide recommendations for clinically relevant models for the various stages of degeneration. There is no one model that replicates the wide range of degenerative changes that occur as part of normal degeneration. However, cyclic overloading replicates many aspects of degeneration, with the advantage of a dose-response allowing the tuning of damage initiated. Models of severe degeneration are currently lacking, but there is potential that combining cyclic overloading and enzymatic digestion will provide model that closely resembles human IVD degeneration. This will provide an effective way to investigate the effects of severe degeneration, and the evaluation of treatments for the IVD, which would generally be indicated at this advanced stage of degeneration.
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22
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Hickman TT, Rathan-Kumar S, Peck SH. Development, Pathogenesis, and Regeneration of the Intervertebral Disc: Current and Future Insights Spanning Traditional to Omics Methods. Front Cell Dev Biol 2022; 10:841831. [PMID: 35359439 PMCID: PMC8963184 DOI: 10.3389/fcell.2022.841831] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/09/2022] [Indexed: 02/06/2023] Open
Abstract
The intervertebral disc (IVD) is the fibrocartilaginous joint located between each vertebral body that confers flexibility and weight bearing capabilities to the spine. The IVD plays an important role in absorbing shock and stress applied to the spine, which helps to protect not only the vertebral bones, but also the brain and the rest of the central nervous system. Degeneration of the IVD is correlated with back pain, which can be debilitating and severely affects quality of life. Indeed, back pain results in substantial socioeconomic losses and healthcare costs globally each year, with about 85% of the world population experiencing back pain at some point in their lifetimes. Currently, therapeutic strategies for treating IVD degeneration are limited, and as such, there is great interest in advancing treatments for back pain. Ideally, treatments for back pain would restore native structure and thereby function to the degenerated IVD. However, the complex developmental origin and tissue composition of the IVD along with the avascular nature of the mature disc makes regeneration of the IVD a uniquely challenging task. Investigators across the field of IVD research have been working to elucidate the mechanisms behind the formation of this multifaceted structure, which may identify new therapeutic targets and inform development of novel regenerative strategies. This review summarizes current knowledge base on IVD development, degeneration, and regenerative strategies taken from traditional genetic approaches and omics studies and discusses the future landscape of investigations in IVD research and advancement of clinical therapies.
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Affiliation(s)
- Tara T. Hickman
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Sudiksha Rathan-Kumar
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Sun H. Peck
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- *Correspondence: Sun H. Peck,
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23
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Alawamry A, Makia MA, Samir MA. Role of intra-discal Vancomycin instillation in prevention post-operative discitis. EGYPTIAN JOURNAL OF NEUROSURGERY 2022. [DOI: 10.1186/s41984-022-00143-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Post discectomy discitis is regarded as the most disabling cause of failed back surgery. Value of local intra-operative application of antibiotics in prevention of such complication has been a matter of debate. We evaluate the role of intraoperative intra-discal vancomycin powder instillation as a prophylaxis in prevention of postoperative discitis in patients undergoing microscopic discectomy. We allocated 100 patients undergoing discectomy equally into two groups. In the first group, a local Vancomycin powder was inserted into the disc space after finishing discectomy, and in the second group, nothing was inserted.
Results
The postoperative discitis was reported in 6 cases; of them, two patients were in the Vancomycin group (4%), while four patients were in the non-Vancomycin group (8%).
Conclusions
We concluded that the intra-operative prophylaxis, with intra-discal Vancomycin, decreased the incidence of postoperative discitis but without significant statistical difference. We advocate using local vancomycin especially in high risk patients for prevention of post discectomy discitis.
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Liang W, Han B, Hai Y, Sun D, Yin P. Mechanism of Action of Mesenchymal Stem Cell-Derived Exosomes in the Intervertebral Disc Degeneration Treatment and Bone Repair and Regeneration. Front Cell Dev Biol 2022; 9:833840. [PMID: 35096846 PMCID: PMC8795890 DOI: 10.3389/fcell.2021.833840] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 12/27/2021] [Indexed: 12/19/2022] Open
Abstract
Exosomes are extracellular vesicles formed by various donor cells that regulate gene expression and cellular function in recipient cells. Exosomes derived from mesenchymal stem cells (MSC-Exos) perform the regulatory function of stem cells by transporting proteins, nucleic acids, and lipids. Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, and it is characterized by a decreased number of nucleus pulposus cells, extracellular matrix decomposition, aging of the annulus fibrosus, and cartilage endplate calcification. Besides, nutrient transport and structural repair of intervertebral discs depend on bone and cartilage and are closely related to the state of the bone. Trauma, disease and aging can all cause bone injury. However, there is a lack of effective drugs against IDD and bone injury. Recent MSC-Exos fine tuning has led to significant progress in the IDD treatment and bone repair and regeneration. In this review, we looked at the uniqueness of MSC-Exos, and the potential treatment mechanisms of MSC-Exos with respect to IDD, bone defects and injuries.
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Affiliation(s)
- Weishi Liang
- Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Bo Han
- Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Yong Hai
- Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Duan Sun
- Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Peng Yin
- Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
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Xu D, Ma X, Sun C, Han J, Zhou C, Wong SH, Chan MTV, Wu WKK. Circular RNAs in Intervertebral Disc Degeneration: An Updated Review. Front Mol Biosci 2022; 8:781424. [PMID: 35071323 PMCID: PMC8770867 DOI: 10.3389/fmolb.2021.781424] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/13/2021] [Indexed: 01/26/2023] Open
Abstract
Low back pain, a common medical condition, could result in severe disability and inflict huge economical and public health burden. Its pathogenesis is attributed to multiple etiological factors, including intervertebral disc degeneration (IDD). Emerging evidence suggests that circular RNAs (circRNAs), a major type of regulatory non-coding RNA, play critical roles in cellular processes that are pertinent to IDD development, including nucleus pulposus cell proliferation and apoptosis as well as extracellular matrix deposition. Increasing number of translational studies also indicated that circRNAs could serve as novel biomarkers for the diagnosis of IDD and/or predicting its clinical outcomes. Our review aims to discuss the recent progress in the functions and mechanisms of newly discovered IDD-related circRNAs.
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Affiliation(s)
- Derong Xu
- Department of Spine Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xuexiao Ma
- Department of Spine Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chong Sun
- Department of Spine Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Jialuo Han
- Department of Spine Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chuanli Zhou
- Department of Spine Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Sunny Hei Wong
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Matthew T V Chan
- Department of Anaesthesia and Intensive Care and Peter Hung Pain Research Institute, The Chinese University of Hong Kong, Hong Kong, China
| | - William K K Wu
- Department of Anaesthesia and Intensive Care and Peter Hung Pain Research Institute, The Chinese University of Hong Kong, Hong Kong, China.,State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China
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Krut Z, Pelled G, Gazit D, Gazit Z. Stem Cells and Exosomes: New Therapies for Intervertebral Disc Degeneration. Cells 2021; 10:cells10092241. [PMID: 34571890 PMCID: PMC8471333 DOI: 10.3390/cells10092241] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 12/12/2022] Open
Abstract
Intervertebral disc degeneration (IVDD) occurs as a result of an imbalance of the anabolic and catabolic processes in the intervertebral disc, leading to an alteration in the composition of the extracellular matrix (ECM), loss of nucleus pulposus (NP) cells, excessive oxidative stress and inflammation. Degeneration of the IVD occurs naturally with age, but mechanical trauma, lifestyle factors and certain genetic abnormalities can increase the likelihood of symptomatic disease progression. IVDD, often referred to as degenerative disc disease (DDD), poses an increasingly substantial financial burden due to the aging population and increasing incidence of obesity in the United States. Current treatments for IVDD include pharmacological and surgical interventions, but these lack the ability to stop the progression of disease and restore the functionality of the IVD. Biological therapies have been evaluated but show varying degrees of efficacy in reversing disc degeneration long-term. Stem cell-based therapies have shown promising results in the regeneration of the IVD, but face both biological and ethical limitations. Exosomes play an important role in intercellular communication, and stem cell-derived exosomes have been shown to maintain the therapeutic benefit of their origin cells without the associated risks. This review highlights the current state of research on the use of stem-cell derived exosomes in the treatment of IVDD.
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Affiliation(s)
- Zoe Krut
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; (Z.K.); (G.P.); (D.G.)
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Gadi Pelled
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; (Z.K.); (G.P.); (D.G.)
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Orthopedics, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Dan Gazit
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; (Z.K.); (G.P.); (D.G.)
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Orthopedics, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Zulma Gazit
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; (Z.K.); (G.P.); (D.G.)
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Orthopedics, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Correspondence:
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Chang MC, Park D. The Effect of Intradiscal Platelet-Rich Plasma Injection for Management of Discogenic Lower Back Pain: A Meta-Analysis. J Pain Res 2021; 14:505-512. [PMID: 33642874 PMCID: PMC7903948 DOI: 10.2147/jpr.s292335] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 12/22/2020] [Indexed: 12/16/2022] Open
Abstract
Objective Although several researches of animal and human subjects have yielded promising results regarding intradiscal injection of platelet-rich plasma (PRP) for the management of intervertebral disc (IVD) pathologies, small sample sizes and unstandardized graft preparation procedures hampered these research efforts. Therefore, we conducted a meta-analysis to evaluate the effectiveness of intradiscal PRP injection for the treatment of discogenic lower back pain. Methods The PubMed, SCOPUS, Embase, and Cochrane Library databases were systematically searched for relevant studies published from January 01, 1980 to December 14, 2020. The keywords used for the search were (platelet-rich plasma) AND (intradiscal OR back pain OR lumbar spine OR discogenic). Filters were used to select studies with human participants; all study designs were included. Results After the systematic review, three articles, including one randomized control trial and two prospective observational studies, were included in the final analysis. Analysis of changes in visual analogue scale (VAS) scores showed that VAS scores were significantly reduced two and six months after intradiscal PRP injection (two months: standardized mean difference [SMD] = −0.837, 95% CI = −1.158 to −0.516, P < 0.001; six months: SMD = −1.430, 95% CI = −2.209 to −0.652, P < 0.001), but not after one month (SMD = −0.661, 95% CI = −1.346 to 0.023, P = 0.058). Regarding changes in Owestry Disability Index (ODI), ODI scores were significantly reduced after six months (SMD = −0.964, 95% CI = −1.885 to −0.043, P = 0.040). Conclusion Intradiscal PRP injections are effective in relieving pain and improving disabilities caused by discogenic lower back pain. However, the pain-reducing effect significantly manifests two or six months after the injections, but not after one month.
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Affiliation(s)
- Min Cheol Chang
- Department of Rehabilitation Medicine, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - Donghwi Park
- Department of Physical Medicine and Rehabilitation, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
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Ma J, Stefanoska D, Stone LS, Hildebrand M, van Donkelaar CC, Zou X, Basoli V, Grad S, Alini M, Peroglio M. Hypoxic stress enhances extension and branching of dorsal root ganglion neuronal outgrowth. JOR Spine 2020; 3:e1090. [PMID: 32613165 PMCID: PMC7323469 DOI: 10.1002/jsp2.1090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/02/2020] [Accepted: 04/07/2020] [Indexed: 12/27/2022] Open
Abstract
It has been shown that painful intervertebral discs (IVDs) were associated with a deeper innervation. However, the effect of the disc's degenerative microenvironment on neuronal outgrowth remains largely unknown. The focus of this study was to determine the influence of hypoxia on dorsal root ganglion (DRG) neurite outgrowth. Toward this aim, the DRG-derived cell line ND7/23 was either directly subjected to 2% or 20% oxygen conditions or exposed to conditioned medium (CM) collected from IVDs cultured under 2% or 20% oxygen. Viability and outgrowth analysis were performed following 3 days of exposure. Results obtained with the cell line were further validated on cultures of rabbit spinal DRG explants and dissociated DRG neurons. Results showed that hypoxia significantly increased neurite outgrowth length in ND7/23 cells, which was also validated in DRG explant and primary cell culture, although hypoxia conditioned IVD did not significantly increase ND7/23 neurite outgrowth. While hypoxia dramatically decreased the outgrowth frequency in explant cultures, it significantly increased collateral sprouting of dissociated neurons. Importantly, the hypoxia-induced decrease of outgrowth frequency at the explant level was not due to inhibition of outgrowth branching but rather to neuronal necrosis. In summary, hypoxia in DRG promoted neurite sprouting, while neuronal necrosis may reduce the density of neuronal outgrowth at the tissue level. These findings may help to explain the deeper neo-innervation found in the painful disc tissue. HIGHLIGHTS Hypoxia promoted elongation and branching of neurite outgrowth at single cell level, but reduced outgrowth density at tissue level, possibly due to hypoxia-induced neuronal necrosis; these findings may help to explain the deeper neo-innervation found in clinically painful tissues.
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Affiliation(s)
- Junxuan Ma
- AO Research Institute DavosDavosSwitzerland
| | - Despina Stefanoska
- AO Research Institute DavosDavosSwitzerland
- Department of Biomedical EngineeringEindhoven University of TechnologyEindhovenThe Netherlands
| | - Laura S. Stone
- Alan Edwards Centre for Research on Pain, Faculty of DentistryMcGill UniversityMontreal, QuebecCanada
| | | | | | - Xuenong Zou
- Department of Spine Surgery, Orthopedic Research InstituteThe First Affiliated Hospital of Sun Yat‐sen UniversityGuangzhouChina
- Guangdong Provincial Key Laboratory of Orthopedics and TraumatologyGuangzhouChina
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