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Lower back pain commonly arises from intervertebral disc (IVD) failure, often caused by deteriorating annulus fibrosus (AF) and/or nucleus pulposus (NP) tissue. High socioeconomic cost, quality of life issues, and unsatisfactory surgical options motivate the rapid development of non-invasive, regenerative repair strategies for lower back pain. This study aims to evaluate the AF regenerative capacity of injectable matrix repair strategy in ex vivo porcine organ culturing using collagen type-I and polycaprolactone nanofibers (PNCOL) with encapsulated fibroblast cells. Upon 14 days organ culturing, the porcine IVDs were assessed using gross optical imaging, magnetic resonance imaging (MRI), histological analysis, and Reverse Transcriptase quantitative PCR (RT-qPCR) to determine the regenerative capabilities of the PNCOL matrix at the AF injury. PNCOL-treated AF defects demonstrated a full recovery with increased gene expressions of AF extracellular matrix markers, including Collagen-I, Aggrecan, Scleraxis, and Tenascin, along with anti-inflammatory markers such as CD206 and IL10. The PNCOL treatment effectively regenerates the AF tissue at the injury site contributing to decreased herniation risk and improved surgical outcomes, thus providing effective non-invasive strategies for treating IVD injuries.
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Electrical Stimulation-Mediated Tissue Healing in Porcine Intervertebral Disc Under Mechanically Dynamic Organ Culture Conditions
Study Design.Porcine intervertebral discs (IVDs) were excised and then drilled to simulate degeneration before being electrically stimulated for 21 days while undergoing mechanical loading. The discs were then analyzed for gene expression and morphology to assess regeneration. Objective.The purpose of this study was to investigate the effectiveness of the electrical stimulation of IVD treatment as an early intervention method in halting the progression of degenerative disc disease using an ex-vivo porcine model. Summary of Background Data.Treatments for degenerative disc disease are limited in their efficacy and tend to treat the symptoms of the disease rather than repairing the degenerated disc itself. There is a dire need for an early intervention treatment that not only halts the progression of the disease but contributes to reviving the degenerated disc. Methods.Lumbar IVDs were extracted from a mature pig within 1 hour of death and were drilled with a 1.5 mm bit to simulate degenerative disc disease. Four IVDs at a time were then cultured in a dynamic bioreactor system under mechanical loading for 21 days, two with and two without the electrical stimulation treatment. The IVDs were assessed using histological analysis, magnetic resonance imaging, and quantitative reverse transcriptase polymerase chain reaction to quantify the effectiveness of the treatment on the degenerated discs. Results.IVDs with electrical stimulation treatment exhibited extensive annular regeneration and prevented herniation of the nucleus pulposus (NP). In contrast, the untreated group of IVDs were unable to maintain tissue integrity and exhibited NP herniation through multiple layers of the annulus fibrosus. Gene expression showed an increase of extracellular matrix markers and antiinflammatory cytokine interleukin-4 (IL-4), while decreasing in pro-inflammatory markers and pain markers in electrically stimulated IVDs when compared to the untreated group. Conclusion.The direct electrical stimulation application in NP of damaged IVDs can be a viable option to regenerate damaged NP and annulus fibrosus tissues.
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- Award ID(s):
- 1916636
- PAR ID:
- 10608938
- Publisher / Repository:
- Wolters Kluwer
- Date Published:
- Journal Name:
- Spine
- Volume:
- 47
- Issue:
- 10
- ISSN:
- 0362-2436
- Page Range / eLocation ID:
- 764 to 772
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1097/BRS.0000000000004331
