Aloin Regulates Matrix Metabolism and Apoptosis in Human Nucleus Pulposus Cells via the TAK1/NF-κB/NLRP3 Signaling Pathway

Intervertebral disc degeneration (IDD) is a degenerative disease that is characterized by decreased matrix synthesis and extra degradation, nucleus pulposus cells (NPCs) apoptosis, and infiltration of inflammatory factors. Aloin, a colored compound from aloe plants, has been shown to be effective against skeletal degenerative diseases, but it is unclear whether it is protective against IDD. Herein, we investigated the role of aloin in NPCs. In our study, the upregulation of proinflammatory factors, apoptosis, and unbalanced matrix metabolism were observed in degenerative NP tissues. We found that aloin had a curative effect on extracellular matrix metabolism and apoptosis in TNF-alpha- (TNF-α-) treated NPCs by inhibiting oxidative stress and the proinflammatory factor expression. Further investigation revealed that aloin treatment suppressed the TAK1/NF-κB pathway. Moreover, the expression level of the NLPR3 inflammasome was downregulated after aloin treatment in TNF-α-treated NPCs. In summary, our results demonstrated that aloin treatment can reverse TNF-α-induced unbalanced matrix metabolism and apoptosis of NPCs via the TAK1/NF-κB/NLRP3 axis. This study supports that aloin can be a promising therapeutic agent for IDD.

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Role of microRNA-15a-5p/Sox9/NF-κB axis in inflammatory factors and apoptosis of murine nucleus pulposus cells in intervertebral disc degeneration

Life Sciences ◽

10.1016/j.lfs.2021.119408 ◽

2021 ◽

pp. 119408

Author(s):

Shujun Zhang ◽

Sheng Song ◽

Yin Zhuang ◽

Jun Hu ◽

Wei Cui ◽

...

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Inflammatory Factors ◽

Nucleus Pulposus Cells

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Overexpression of miR-150 Inhibits the NF-κB Signal Pathway in Intervertebral Disc Degeneration through Targeting P2X7

Cells Tissues Organs ◽

10.1159/000503281 ◽

2019 ◽

Vol 207 (3-4) ◽

pp. 165-176

Author(s):

Yan Zhang ◽

Yi-Shu Zhang ◽

Xiao-Juan Li ◽

Chao-Rong Huang ◽

Hui-Jin Yu ◽

...

Keyword(s):

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Intervertebral Disc Degeneration ◽

Signal Pathway ◽

Nucleus Pulposus Cells ◽

Tnf Α ◽

Collagen Ii ◽

Cox 2

Objective: To elaborate the mechanism of miR-150 in the regulation of the NF-κB signal pathway in intervertebral disc degeneration (IDD) by targeting P2X7. Methods: The degenerative and normal intervertebral disc tissues were collected to detect the expressions of miR-150 and P2X7. Nucleus pulposus cells were transfected and divided into different groups. Cell apoptosis was determined by flow cytometry and TUNEL staining. The expressions of IL-6, TNF-α, MMP-3, MMP-13, Cox-2, iNOS, collagen II and aggrecan, as well as NF-κB-associated proteins were measured by qRT-PCR and Western blotting. Furthermore, IDD rat models were established to validate the role of miR-150 in vivo.Results: miR-150 was down-regulated but P2X7 was up-regulated in the degenerative intravertebral disc tissues. The apoptosis of nucleus pulposus cells in the IL-1β-induced group with the transfection of miR-150 mimic and siP2X7 was significantly decreased, with reduced levels of IL-6, TNF-α, MMP-3, MMP-13, Cox-2 and iNOS, increased levels of collagen II and aggrecan, as well as decreased P2X7, p-p65/p65 and cleaved caspase-3. However, the above factors showed an opposite tendency after treatment with miR-150 inhibitor. Furthermore, the P2X7 siRNA transfection could reverse the effects caused by miR-150 inhibitor. Simultaneously, pcDNA P2X7 transfection also inhibited the function of miR-150 mimic in IL-1β-induced nucleus pulposus cells. In vivoexperiments further verified the protective role of miR-150 in IDD rats. Conclusion: miR-150 may alleviate the degeneration of the intervertebral disc partially since it could restrict the NF-κB pathway by targeting P2X7, and thereby inhibiting IL-1β-induced matrix catabolism, inflammatory responses and apoptosis of the nucleus pulposus cells.

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LncRNA GAS5 as miR-26a-5p Sponge Regulates the PTEN/PI3K/Akt Axis and Affects Extracellular Matrix Synthesis in Degenerative Nucleus Pulposus Cells in vitro

Frontiers in Neurology ◽

10.3389/fneur.2021.653341 ◽

2021 ◽

Vol 12 ◽

Author(s):

Liang Tan ◽

Yifang Xie ◽

Ye Yuan ◽

Kai Hu

Keyword(s):

Extracellular Matrix ◽

Nucleus Pulposus ◽

Intervertebral Disc Degeneration ◽

Nucleus Pulposus Cell ◽

Nucleus Pulposus Cells ◽

Akt Inhibitor ◽

Matrix Synthesis ◽

Lncrna Gas5

The role of lncRNA growth arrest specific 5 (GAS5) in degenerative nucleus pulposus cell (NPC) apoptosis has been reported, but the mechanism of GAS5 in extracellular matrix (ECM) synthesis in intervertebral disc degeneration (IDD) remains unknown. We aimed to investigate the mechanism of GAS5 in ECM synthesis in degenerative NPCs. GAS5 expression was measured in degenerative NPCs (CP-H170) and normal NPCs (CP-H097). siRNA-mediated GAS5 knockdown was transfected to NPCs to detect cell viability and the expression of ECM-related genes (Collagen II, aggrecan, Collagen I, and MMP-3). Subcellular localization of GAS5 was analyzed. The downstream gene and pathway of GAS5 in degenerative NPCs were explored. As our results indicated, lncRNA GAS5 was upregulated in degenerative NPCs. Silencing GAS5 improved the viability of degenerative NPCs and increased ECM synthesis. GAS5 was mainly located in the cytoplasm of NPCs. LncRNA GAS5 sponged miR-26a-5p to regulate PTEN. Overexpression of miR-26a-5p promoted ECM synthesis in degenerative NPCs. Akt inhibitor LY294002 reversed the promotion of silencing GAS5 on ECM synthesis of degenerative NPCs. In conclusion, lncRNA GAS5 sponged miR-26a-5p to upregulate PTEN and inhibit the PI3K/Akt pathway, thus inhibiting ECM synthesis of degenerative NPCs.

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LIPUS inhibits inflammation and catabolism through the NF‐κB pathway in human degenerative nucleus pulposus cells

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02739-1 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Weiwei Yi ◽

Qing Chen ◽

Chuan Liu ◽

Kaiting Li ◽

Bailong Tao ◽

...

Keyword(s):

Protein Expression ◽

Real Time ◽

Signaling Pathway ◽

Nucleus Pulposus ◽

Real Time Pcr ◽

Inflammatory Factors ◽

Nucleus Pulposus Cells ◽

Tnf Α ◽

Gene And Protein Expression ◽

Collagen Ii

Abstract Background Low-intensity pulsed ultrasound (LIPUS) is a safe and noninvasive rehabilitative physical therapy with anti-inflammatory effects. The current study investigated the effect of LIPUS on the inflammation of nucleus pulposus (NP) cells and its underlying mechanism. Methods Human NP cells were acquired from lumbar disc herniation tissue samples and cultured for experiments. Human NP cells were treated with LPS and then exposed to LIPUS (15 mW/cm2, 30 mW/cm2 and 60 mW/cm2) for 20 min daily for 3 days to determine the appropriate intensity to inhibit the expression of the inflammatory factors TNF-α and IL-1β. The gene and protein expression of aggrecan, collagen II, MMP-3 and MMP-9 was measured by real‐time PCR and western blotting, respectively. The activity of the nuclear factor‐kappa B (NF‐κB) pathway was examined by western blotting and immunofluorescence. After pretreatment with the NF-κB inhibitor PDTC, the expression of TNF-α, IL-1β, MMP-3 and MMP-9 was measured by real‐time PCR. Results LIPUS at intensities of 15 mW/cm2, 30 mW/cm2 and 60 mW/cm2 inhibited LPS-induced NP cell expression of the inflammatory factors TNF-α and IL-1β, especially at 30 mW/cm2. LIPUS significantly upregulated the gene and protein expression of aggrecan and collagen II and downregulated the gene and protein expression of MMP-3 and MMP-9 in LPS-induced NP cells. The NF‐κB signaling pathway was inhibited by LIPUS through inhibiting the protein expression of p-P65 and the translocation of P65 into the nucleus in LPS-induced NP cells. In addition, LIPUS had similar effects as the NF-κB inhibitor PDTC by inhibiting the NF-κB signaling pathway, inflammation and catabolism in LPS-induced human degenerative nucleus pulposus cells. Conclusion LIPUS inhibited inflammation and catabolism through the NF‐κB pathway in human degenerative nucleus pulposus cells.

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The expression of Fas ligand on normal and stabbed-disc cells in a rabbit model of intervertebral disc degeneration: a possible pathogenesis

Journal of Neurosurgery Spine ◽

10.3171/spi.2007.6.5.425 ◽

2007 ◽

Vol 6 (5) ◽

pp. 425-430 ◽

Cited By ~ 25

Author(s):

Jing Wang ◽

Tiansi Tang ◽

Huilin Yang ◽

Xiaoshen Yao ◽

Liang Chen ◽

...

Keyword(s):

Nucleus Pulposus ◽

Intervertebral Disc Degeneration ◽

Fas Ligand ◽

Rabbit Model ◽

Nucleus Pulposus Cells ◽

Physiological Barrier ◽

Disc Cells ◽

The Mean ◽

Privileged Site

Object The nucleus pulposus has been reported to be an immunologically privileged site. The expression of Fas ligand (FasL) on normal and herniated lumbar disc cells has been reported. The relationship between a physiological barrier and the role of FasL has not yet been addressed. To clarify this relationship and to investigate a possible pathogenesis of intervertebral disc degeneration (IDD), the expression of Fas and FasL (a mean apoptosis index) on normal and stabbed-disc cells was examined in a rabbit model of IDD. Methods Using defined needle gauges and depths, the anular puncture model of IDD was established in rabbits. The normal and stabbed discs were harvested at 3, 6, and 10 weeks after surgery. Immunohistochemical staining of these discs for Fas and FasL was performed using standard procedures. The mean apoptosis indices of the disc cells were determined using flow cytometry analysis. The nucleus pulposus cells from the normal discs exhibited relatively weak immunopositivity, whereas the nucleus pulposus cells from the stabbed discs exhibited strong immunopositivity. There was a significant difference (p < 0.001) in the percentage of FasL-positive nucleus pulposus cells between the normal discs and the stabbed discs. The mean apoptosis indices of the stabbed-disc cells at 3, 6, and 10 weeks poststab were significantly higher than those in normal disc cells (p < 0.001, 0.002, and 0.006, respectively). There was a significant correlation between the degree of FasL-positive expression and the degree of Fas-positive expression of the nucleus pulposus cells poststab (r = 0.571, p = 0.0036). Conclusions These observations indicate that the nucleus pulposus is an immunologically privileged site. This immunological privilege is maintained by FasL and the physiological barrier together. When the physiological barrier was damaged (by stabbing the disc), the role of FasL changed, and FasL was coexpressed with Fas to induce apoptosis of disc cells. These results indicate that an autoimmune reaction may be a possible pathogenesis of IDD.

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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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