Mechanism of Long Noncoding RNA HOTAIR in Nucleus Pulposus Cell Autophagy and Apoptosis in Intervertebral Disc Degeneration

Objective. Intervertebral disc degeneration (IDD) contributes to cervical and lumbar diseases. Long noncoding RNAs (lncRNAs) are implicated in IDD. This study explored the mechanism of lncRNA HOTAIR in IDD. Methods. Normal and degenerative nucleus pulposus (NP) cells were isolated from NP tissues obtained in intervertebral disc surgery. Cell morphology was observed by immunocytochemistry staining and toluidine blue staining. NP cell markers were detected by RT-qPCR. Proliferation was detected by MTT assay. Autophagy-related proteins were detected by Western blot. Autophagosome was observed by monodansylcadaverine fluorescence staining. Apoptosis was detected by TUNEL staining and flow cytometry. si-HOTAIR and/or miR-148a inhibitor was introduced into degenerative NP cells. Binding relationships among HOTAIR, miR-148a, and PTEN were predicted and verified by dual-luciferase reporter assay and RNA pull-down. Finally, IDD rat models were established. Rat caudal intervertebral discs were assessed by HE staining. Expressions of HOTAIR, miR-148a, and PTEN were determined by RT-qPCR. Results. HOTAIR was highly expressed in degenerative NP cells p < 0.05 . si-HOTAIR inhibited degenerative NP cell apoptosis and autophagy p < 0.05 . HOTAIR upregulated PTEN as a sponge of miR-148a. miR-148a was poorly expressed in degenerative NP cells. miR-148a deficiency partially reversed the inhibition of si-HOTAIR on degenerative NP cell autophagy and apoptosis (all p < 0.05 ). In vivo assay confirmed that si-HOTAIR impeded autophagy and apoptosis in intervertebral disc tissues, thus improving pathological injury in IDD rats (all p < 0.05 ). Conclusion. LncRNA HOTAIR promoted NP cell autophagy and apoptosis via promoting PTEN expression as a ceRNA of miR-148a in IDD.

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MiR-125a Rs12976445 Polymorphism is Associated with the Apoptosis Status of Nucleus Pulposus Cells and the Risk of Intervertebral Disc Degeneration

Cellular Physiology and Biochemistry ◽

10.1159/000438630 ◽

2016 ◽

Vol 38 (1) ◽

pp. 295-305 ◽

Cited By ~ 11

Author(s):

Jin Feng Ma ◽

Li Na Zang ◽

Yong Ming Xi ◽

Wen Jiu Yang ◽

Debo Zou

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Minor Allele ◽

Expression Level ◽

Luciferase Assay ◽

Luciferase Reporter ◽

Degenerative Diseases ◽

Nucleus Pulposus Cells

Background: Spinal degenerative diseases are a major health problem and social burden worldwide. Intervertebral disc degeneration (IDD) is the pathological basis of spinal degenerative diseases and is characterized by loss of nucleus pulposus cells due to excessive apoptosis caused by various factors. MicroRNAs (miRNAs) have been reported to be functionally involved in the control of apoptosis. Methods: computational analysis and luciferase assay were used to identify the target of miR-125a, and cell culture, transfection were used to confirm such relationship. Sequencing was used to determine the genotype of each participant. Results: We confirmed the previous report that the presence of the minor allele (T) of rs12976445 polymorphism significantly downregulated the expression level of miR-125a in nucleus pulposus cells, leading to less efficient inhibition of its target gene. We also validated TP53INP1 as a target of miR-125a in nucleus pulposus cells using a dual luciferase reporter system, and the transfection of miR-125a significantly reduced the expression of TP53INP1. The expression level of TP53INP1 was significantly lower in nucleus pulposus cells genotyped as CT or TT than in those genotyped as CC, and the apoptosis rate was consistently lower in the CC group than in the nucleus pulposus cells collected from individuals carrying at least one minor allele of rs12976445 polymorphism. To study the association between rs12976445 polymorphism and the risk of IDD, we enrolled 242 patients diagnosed with IDD and 278 normal controls, and significant differences were noted regarding the genotype distribution of rs12976445 between the IDD and the control groups (OR = 2.69, 95% C.I. = 1.88-3.83, p < 0.0001). In summary, rs12976445 polymorphism is significantly associated with the risk of IDD in the Chinese population. Conclusion: The present study indicated that miR-125a is a promising potential target for patients with IDD in clinical practice.

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Protective Effect of Polygonatum sibiricum Polysaccharides on Apoptosis, Inflammation, and Oxidative Stress in Nucleus Pulposus Cells of Rats with the Degeneration of the Intervertebral Disc

International Journal of Polymer Science ◽

10.1155/2019/8925807 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Zhaohui Zhai ◽

Zhaoxin Li ◽

Zhonglei Ji ◽

Xiaosheng Lu

Keyword(s):

Oxidative Stress ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Rat Model ◽

Intervertebral Disc Degeneration ◽

Intervertebral Discs ◽

New Drugs ◽

Nucleus Pulposus Cells ◽

And Oxidative Stress

Objective. Polygonatum sibiricum polysaccharide (PSP) has antioxidant activity, immune enhancement, and other biological properties. However, the effect of PSP on intervertebral disc degeneration has not been reported. In this study, we mainly investigated the effect of PSP on the apoptosis, inflammation, and oxidative stress of nucleus pulposus cells (NPCs) during the process of intervertebral disc degeneration. Methods. A rat NPC model induced by H2O2 was constructed. The CCK8 method was used to measure the effects of PSP on the apoptosis of rat NPCs induced by H2O2. The effects on the activity of SOD and content of MDA were also determined. The rat model of intervertebral disc degeneration was treated with PSP for 1 month, and the mRNA expression levels of IL-1β, COX2, iNOS, Col2α1, Col10α1, and MMP3 were measured by qPCR in the tissue of intervertebral disc. NPCs from the degenerated intervertebral discs were separated, and the cell viability was measured by the CCK8 method. The contents of SOD and MDA in NPCs were determined as well. Results. PSP significantly reduced the apoptosis of NPCs induced by H2O2, significantly increased the SOD content, and decreased the content of MDA in H2O2-induced NPCs. The expression level of IL-1β, COX2, and iNOS in the rat model with intervertebral disc degeneration was significantly downregulated after 1 month of PSP treatment. PSP treatment increased the expression of Col2α1 type and significantly decreased the expression of Col10α1 type collagen and MMP3 in rats with disc degeneration. PSP treatment significantly reduced NPC apoptosis and increased its SOD content and reduced MDA content, which is consistent with the results from cell-level experiments. Conclusion. PSP can effectively reduce the apoptosis, inflammation, and oxidative stress of H2O2-induced NPCs in rats with intervertebral disc degeneration and mitigate the progression of intervertebral disc degeneration, which has the potential to be developed as new drugs for the treatment of intervertebral disc degeneration.

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Mangiferin Alleviates Mitochondrial ROS in Nucleus Pulposus Cells and Protects against Intervertebral Disc Degeneration via Suppression of NF-κB Signaling Pathway

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/6632786 ◽

2021 ◽

Vol 2021 ◽

pp. 1-27

Author(s):

Haichao Yu ◽

Guowei Hou ◽

Jiankang Cao ◽

Yanyu Yin ◽

Yunpeng Zhao ◽

...

Keyword(s):

Intervertebral Disc ◽

Mitochondrial Dysfunction ◽

Signaling Pathway ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Intervertebral Discs ◽

Nucleus Pulposus Cells ◽

Mitochondrial Ros ◽

Tnf Α

Intervertebral disc degeneration (IVDD), one of the most common clinical diseases worldwide, causes disc herniation and sciatica. Recent studies have identified the involvement of mitochondrial dysfunction, inflammatory responses, and extracellular matrix degradation in IVDD. Mangiferin is known to protect against various diseases by inhibiting oxidative stress, suppressing inflammation reaction, and relieving mitochondrial dysfunction. Whether mangiferin can alleviate IVDD remains to be elucidated. In the present study, human nucleus pulposus cells (HNPCs) and mouse intervertebral discs were cultured and stimulated with TNF-α, with or without treatment of mangiferin. Moreover, we established a rat needle puncture model and injected mangiferin into the intervertebral discs to verify its protective effect on IVDD. Furthermore, the activity of the NF-κB signaling pathway was tested in vitro. Our results indicated that mangiferin alleviated the inflammatory response and reversed the loss of major intervertebral disc components. Besides, mangiferin reduced reactive oxygen species production, ameliorated mitochondrial damage, and decreased the expression of apoptosis-related parameters in stimulation of TNF-α. In addition, mangiferin antagonized the activation of the NF-κB signaling pathway induced by TNF-α. Collectively, mangiferin antagonized mitochondrial ROS in NP cells and protected against IVDD by suppressing the activation of the NF-κB signaling pathway, which might provide a potential therapeutic instrument for IVDD.

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Intervertebral Disc Degeneration in Warmblood Horses: Morphology, Grading, and Distribution of Lesions

Veterinary Pathology ◽

10.1177/0300985817747950 ◽

2018 ◽

Vol 55 (3) ◽

pp. 442-452 ◽

Cited By ~ 10

Author(s):

Wilhelmina Bergmann ◽

Niklas Bergknut ◽

Stefanie Veraa ◽

Andrea Gröne ◽

Hans Vernooij ◽

...

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Clinical Relevance ◽

Annulus Fibrosus ◽

Intervertebral Disc Degeneration ◽

Thoracolumbar Spine ◽

Intervertebral Discs ◽

Vertebral Bone ◽

Cleft Formation

Equine intervertebral disc degeneration is thought to be rare and of limited clinical relevance, although research is lacking. To objectively assess pathological changes of the equine intervertebral disc and their clinical relevance, description of the normal morphology and a practical, biologically credible grading scheme are needed. The objectives of this study are to describe the gross and histological appearance of the equine intervertebral discs and to propose a grading scheme for macroscopic degeneration. Spinal units from 33 warmblood horses were grossly analyzed and scored. Of the 286 intervertebral discs analyzed, 107 (37%) were assigned grade 1 and grade 2 (considered normal) and were analyzed histologically. A nucleus pulposus and an annulus fibrosus could be identified macroscopically and histologically. Histologically, the nucleus pulposus was composed of a cartilaginous matrix and the annulus fibrosus of parallel collagenous bands. A transition zone was also histologically visible. Intra- and inter-observer reliability scores were high for all observers. Higher grades were associated with greater age. Gross changes associated with equine intervertebral disc degeneration (grades 3–5)—that is, yellow discoloration, cleft formation (tearing), and changes in consistency of the nucleus pulposus—were largely similar to those in humans and dogs and were most prevalent in the caudal cervical spine. Equine intervertebral disc degeneration was not associated with osteophyte formation. Changes of the vertebral bone were most common in the thoracolumbar spine but were not correlated with higher grades of intervertebral disc degeneration. Thus, changes of the vertebral bone should be excluded from grading for equine intervertebral disc degeneration.

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MiR-25 Protects Against Apoptosis of Nucleus Pulposus Cells by Targeting SUMO2 in Intervertebral Disc Degeneration

10.21203/rs.3.rs-63482/v1 ◽

2020 ◽

Author(s):

Lei Changbin ◽

Li Jiang ◽

Tang Guang ◽

Wang Jiong ◽

Hongsheng Lin

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Luciferase Reporter ◽

Nucleus Pulposus Cells ◽

P53 Signaling ◽

Pulldown Assay ◽

Signaling Axis ◽

Incorporation Assay

Abstract Background MiR-25 was reported to be down-regulated in patients with intervertebral disc degeneration (IDD). However, the potential role of miR-25 in IDD remained unclear. Therefore, the present study aimed to investigate the effects of miR-25 on human intervertebral disc nucleus pulposus cells (NPCs).Methods We evaluated the expression of miR-25 and small ubiquitin-related modifier 2 (SUMO2) in human nucleus pulposus (NP) tissues by real-time PCR and western blotting. Then, the target relationship between miR-25 and SUMO2 was validated by luciferase reporter assay and biotin-coupled miRNA pulldown assay. The potential roles of miR-25 in NPC proliferation and apoptosis were confirmed using CCK-8 assay, EdU incorporation assay, and flow cytometry.Results MiR-25 was lowly expressed in the patients with IDD. In addition, miR-25 facilitated the growth of NPCs by increasing cell proliferation and inhibiting apoptosis. Furthermore, we elucidated that SUMO2 was a target gene of miR-25, and was regulated by miR-25 through p53 signaling pathway. Restore of SUMO2 expression abrogated the effects of miR-25 on NPCs.Conclusion MiR-25 promoted the proliferation, inhibited the apoptosis of NPCs, and suppressed the development of IDD via SUMO2-mediated p53 signaling axis.

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Promoting Nrf2/Sirt3-Dependent Mitophagy Suppresses Apoptosis in Nucleus Pulposus Cells and Protects against Intervertebral Disc Degeneration

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/6694964 ◽

2021 ◽

Vol 2021 ◽

pp. 1-20

Author(s):

Sunli Hu ◽

Chenxi Zhang ◽

Tianchen Qian ◽

Yue Bai ◽

Liang Chen ◽

...

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Protein Docking ◽

Tunel Staining ◽

Autophagic Flux ◽

Potential Candidate ◽

Nucleus Pulposus Cells

One of the causes of intervertebral disc degeneration (IVDD) is nucleus pulposus cell (NPC) death, possibly apoptosis. In this study, we explored the role of the Nrf2/Sirt3 pathway and tert-butylhydroquinone (t-BHQ) in IVDD and elucidated the potential working mechanism. Reactive oxygen species (ROS) assay kits and malondialdehyde (MDA) assay kits were used to assess oxidative stress. Western blot and TUNEL staining were used to examine apoptosis. After siRNA against Nrf2 or lentivirus against Sirt3 was transfected into NPCs, the mechanism of the effect of the Nrf2/Sirt3 pathway on NPCs was assessed. The interaction between t-BHQ and its potential interacting protein NRF2 was further investigated through protein docking analysis. ChIP examined the binding affinity between Nrf2 and Sirt3 promoter. In vivo experiments, X-ray, hematoxylin-eosin (HE) staining, Safranin O staining, and immunohistochemistry were used to evaluate IVDD grades. The results demonstrated that activation of the Nrf2/Sirt3 pathway inhibited tert-butyl hydroperoxide- (TBHP-) induced apoptosis and mitochondrial dysfunction in vitro. In addition to apoptosis, upregulation of the Nrf2/Sirt3 pathway induced by t-BHQ restored TBHP-induced autophagic flux disturbances. However, its protective effect was reversed by chloroquine and Si-ATG5. Furthermore, t-BHQ ameliorated IVDD development in a rat model. In conclusion, our findings indicate that the Nrf2/Sirt3 pathway and its agonist represent a potential candidate for treating IVDD.

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Effects of microRNA-27a Targeting Smad1 on Intervertebral Disc Degeneration and Biological Characteristics of Nucleus Pulposus Cells

10.21203/rs.3.rs-99036/v1 ◽

2020 ◽

Author(s):

Heng-Tao Tang ◽

Song Zhang ◽

Xin-Chang Lu ◽

Tong-Yu Geng

Keyword(s):

Cell Proliferation ◽

Inflammatory Response ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Biological Characteristics ◽

Luciferase Reporter ◽

Ecm Proteins ◽

Reporter Assays

Abstract Objective: The present study aimed to analyze the expression of microRNA-27a (miR-27a) in intervertebral disc degeneration (IDD) and its effect on the biological characteristics of nucleus pulposus (NP) cells. Methods: An IDD rat model was established, and the expression of miR-27a and Smad1 in the intervertebral disc tissue was detected. An oxygen and glucose deprivation (OGD) NP cell model was established to simulate the IDD microenvironment, and the effects of downregulated miR-27a on the proliferation, apoptosis, inflammatory response, and extracellular matrix (ECM) proteins of OGD-NP cells were analyzed. The target relationship of miR-27a and Smad1 was verified by luciferase reporter assays, and siRNA-Smad1 was transfected to reverse the experiment. Results: The level of miR-27a in the IDD model group was significantly increased, whereas that of Smad1 was decreased compared with the sham group (P<0.05). Inhibition of miR-27a improved cell proliferation, and inhibited apoptosis, degradation of the ECM, and inflammatory response of OGD-NP cells compared with the OGD group (P<0.05). The results of the double luciferase reporter assays indicated that Smad1 was the target gene of miR-27a. Smad1 silencing reversed the increase in ECM proteins induced by inhibition of miR-27a; However, it did not affect cell proliferation and apoptosis. Conclusion: The expression levels of miR-27a were upregulated in IDD and it may be involved in the progression of IDD by promoting the apoptosis of NP cells and ECM degradation by targeting Smad1.

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Disordered Mechanical Stress and Tissue Engineering Therapies in Intervertebral Disc Degeneration

Polymers ◽

10.3390/polym11071151 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1151 ◽

Cited By ~ 5

Author(s):

Runze Zhao ◽

Wanqian Liu ◽

Tingting Xia ◽

Li Yang

Keyword(s):

Tissue Engineering ◽

Back Pain ◽

Intervertebral Disc ◽

Mechanical Stress ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Annulus Fibrosus ◽

Intervertebral Disc Degeneration ◽

Intervertebral Discs ◽

Body Motion

Low back pain (LBP), commonly induced by intervertebral disc degeneration, is a lumbar disease with worldwide prevalence. However, the mechanism of degeneration remains unclear. The intervertebral disc is a nonvascular organ consisting of three components: Nucleus pulposus, annulus fibrosus, and endplate cartilages. The disc is structured to support our body motion and endure persistent external mechanical pressure. Thus, there is a close connection between force and intervertebral discs in LBP. It is well established that with aging, disordered mechanical stress profoundly influences the fate of nucleus pulposus and the alignment of collagen fibers in the annulus fibrosus. These support a new understanding that disordered mechanical stress plays an important role in the degeneration of the intervertebral discs. Tissue-engineered regenerative and reparative therapies are being developed for relieving disc degeneration and symptoms of lower back pain. In this paper, we will review the current literature available on the role of disordered mechanical stress in intervertebral disc degeneration, and evaluate the existing tissue engineering treatment strategies of the current therapies.

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Expression of miR-195 and its target gene Bcl-2 in human intervertebral disc degeneration and their effects on nucleus pulposus cell apoptosis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02538-8 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Xue-Lin Lin ◽

Zhao-Yun Zheng ◽

Qing-Shan Zhang ◽

Zhen Zhang ◽

You-Zhi An

Keyword(s):

Cell Proliferation ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Rat Model ◽

Cell Apoptosis ◽

Intervertebral Disc Degeneration ◽

Target Gene ◽

Blank Group ◽

Tnf Α

Abstract Objective To investigate the expression of miR-195 and its target gene Bcl-2 in intervertebral disc degeneration (IVDD) and its effect on nucleus pulposus (NP) cell apoptosis. Methods The expressions of miR-195 and Bcl-2 in NP tissues of IVDD patients were quantified by qRT-PCR and western blotting, respectively. NP cells were divided into blank group, TNF-α group, TNF-α + miR-NC group, TNF-α + siBcl-2 group, and TNF-α + miR-195 inhibitors + siBcl-2 group. Cell proliferation was detected by MTT assay, cell apoptosis evaluated by flow cytometry, and mitochondrial membrane potential (MMP) tested by JC-1 staining. Moreover, the function of miR-195 on IVDD in vivo was investigated using a puncture-induced IVDD rat model. Results IVDD patients had significantly increased miR-195 expression and decreased Bcl-2 protein expression in NP tissues. The expression of miR-195 was negatively correlated with the expression of Bcl-2 in IVDD patients. Dual-luciferase reporter gene assay indicated that Bcl-2 was a target gene of miR-195. In comparison with blank group, TNF-α group showed decreased cell proliferation and MMP, increased cell apoptosis, upregulated expression of miR-195, Bax, and cleaved caspase 3, and downregulated Bcl-2 protein, while these changes were attenuated by miR-195 inhibitors. Additionally, siBcl-2 can reverse the protective effect of miR-195 inhibitors on TNF-α-induced NP cells. Besides, inhibition of miR-195 alleviated IVDD degeneration and NP cell apoptosis in the rat model. Conclusion MiR-195 was significantly upregulated in NP tissues of IVDD patients, and inhibition of miR-195 could protect human NP cells from TNF-α-induced apoptosis via upregulation of Bcl-2.

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