scholarly journals Magnoflorine Alleviates “M1” Polarized Macrophage-Induced Intervertebral Disc Degeneration Through Repressing the HMGB1/Myd88/NF-κB Pathway and NLRP3 Inflammasome

2021 ◽  
Vol 12 ◽  
Author(s):  
Feng Zhao ◽  
Zhenye Guo ◽  
Fushan Hou ◽  
Wei Fan ◽  
Binqiang Wu ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Cell Viability ◽  
Disc Degeneration ◽  
Inflammatory Cytokines ◽  
Nlrp3 Inflammasome ◽  
Cell Apoptosis ◽  
Intervertebral Disc Degeneration ◽  
Catabolic Enzymes ◽  
Related Proteins ◽  
Pro Inflammatory Cytokines

Intervertebral disc degeneration (IDD) is related to the deterioration of nucleus pulposus (NP) cells due to hypertrophic differentiation and calcification. The imbalance of pro-inflammatory (M1 type) and anti-inflammatory (M2 type) macrophages contributes to maintaining tissue integrity. Here, we aimed to probe the effect of Magnoflorine (MAG) on NP cell apoptosis mediated by “M1” polarized macrophages. THP-1 cells were treated with lipopolysaccharide (LPS) to induce “M1” polarized macrophages. Under the treatment with increasing concentrations of MAG, the expression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-18), high mobility group box protein 1 (HMGB1), as well as myeloid differentiation factor 88 (MyD88), nuclear factor kappa B (NF-κB) and NOD-like receptor 3 (NLRP3) inflammasomes in THP-1 cells were determined. What’s more, human NP cells were treated with the conditioned medium (CM) from THP-1 cells. The NP cell viability and apoptosis were evaluated. Western blot (WB) was adopted to monitor the expression of apoptosis-related proteins (Bax, Caspase3, and Caspase9), catabolic enzymes (MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5), and extracellular matrix (ECM) compositions (collagen II and aggrecan) in NP cells. As a result, LPS evidently promoted the expression of pro-inflammatory cytokines and HMGB1, the MyD88-NF-κB activation, and the NLRP3 inflammasome profile in THP-1 cells, while MAG obviously inhibited the "M1″ polarization of THP-1 cells. After treatment with “M1” polarized THP-1 cell CM, NP cell viability was decreased, while cell apoptosis, the pro-inflammatory cytokines, apoptosis-related proteins, and catabolic enzymes were distinctly up-regulated, and ECM compositions were reduced. After treatment with MAG, NP cell damages were dramatically eased. Furthermore, MAG dampened the HMGB1 expression and inactivated the MyD88/NF-κB pathway and NLRP3 inflammasome in NP cells. In conclusion, this study confirmed that MAG alleviates “M1” polarized macrophage-mediated NP cell damage by inactivating the HMGB1-MyD88-NF-κB pathway and NLRP3 inflammasome, which provides a new reference for IDD treatment.

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

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.

scholarly journals Elevated lymphotoxin-α (TNFβ) is associated with intervertebral disc degeneration

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhu Guo ◽  
Chensheng Qiu ◽  
Christina Mecca ◽  
Yang Zhang ◽  
Jiang Bian ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Cell Viability ◽  
Disc Degeneration ◽  
Intervertebral Disc Degeneration ◽  
Caspase 3 ◽  
Type Ii Collagen ◽  
Type Ii ◽  
Optimal Conditions ◽  
Cell Degeneration ◽  
Lymphotoxin Α

Abstract Background Intervertebral disc degeneration (IVDD) is a primary cause of degenerative disc diseases; however, the mechanisms underlying the degeneration remain unclear. The immunoinflammatory response plays an important role in IVDD progression. The inflammatory cytokine lymphotoxin-α (LTα), formerly known as TNFβ, is associated with various pathological conditions, while its role in the pathogenesis of IVDD remains elusive. Methods Real-time quantitative polymerase chain reaction (RT-qPCR), Western blotting (WB), and enzyme-linked immunosorbent assays were used to assess the levels of LTα in human nucleus pulposus (NP) tissues between degeneration and control groups. The plasma concentrations of LTα and C-reactive protein (CRP) were compared between healthy and IVDD patients. Rat primary NP cells were cultured and identified via immunofluorescence. Methyl-thiazolyl-tetrazolium assays and flow cytometry were used to evaluate the effects of LTα on rat NP cell viability. After NP cells were treated with LTα, degeneration-related molecules (Caspase-3, Caspase-1, matrix metalloproteinase (MMP) -3, aggrecan and type II collagen) were measured via RT-qPCR and WB. Results The levels of both the mRNA and protein of LTα in human degenerated NP tissue significantly increased. Plasma LTα and CRP did not differ between healthy controls and IVDD patients. Rat primary NP cells were cultured, and the purity of primary NP cells was > 90%. Cell experiments showed inversely proportional relationships among the LTα dose, treatment time, and cell viability. The optimal conditions (dose and time) for LTα treatment to induce rat NP cell degeneration were 5 μg/ml and 48 ~ 72 h. The apoptosis rate and the levels of Caspase-3, Caspase-1, and MMP-3 significantly increased after LTα treatment, while the levels of type II collagen and aggrecan were decreased, and the protein expression levels were consistent with their mRNA expression levels. Conclusions This study demonstrated that elevated LTα is closely associated with IVDD and that LTα may induce NP cell apoptosis and reduce important extracellular matrix (ECM) proteins, which cause adverse effects on IVDD progress. Moreover, the optimal conditions for LTα treatment to induce NP cell degeneration were determined.

scholarly journals Synergistic Effects of Acidic pH and Pro-Inflammatory Cytokines IL-1β and TNF-α for Cell-Based Intervertebral Disc Regeneration

2020 ◽  
Vol 10 (24) ◽  
pp. 9009
Author(s):  
Chiara Borrelli ◽  
Conor T. Buckley
Keyword(s):  
Intervertebral Disc ◽  
Cell Viability ◽  
Inflammatory Cytokines ◽  
Cell Function ◽  
Synergistic Effects ◽  
Dominant Factor ◽  
Disc Regeneration ◽  
Tnf Α ◽  
Intervertebral Disc Regeneration ◽  
Pro Inflammatory Cytokines

The intervertebral disc (IVD) relies mainly on diffusion through the cartilaginous endplates (CEP) to regulate the nutrient and metabolites exchange, thus creating a challenging microenvironment. Degeneration of the IVD is associated with intradiscal acidification and elevated levels of pro-inflammatory cytokines. However, the synergistic impact of these microenvironmental factors for cell-based therapies remains to be elucidated. The aim of this study was to investigate the effects of low pH and physiological levels of interleukin-1ß (IL-1β) and tumour necrosis factor-α (TNF-α) on nasal chondrocytes (NCs) and subsequently compare their matrix forming capacity to nucleus pulposus (NP) cells in acidic and inflamed culture conditions. NCs and NP cells were cultured in low glucose and low oxygen at different pH conditions (pH 7.1, 6.8 and 6.5) and supplemented with physiological levels of IL-1β and TNF-α. Results showed that acidosis played a pivotal role in influencing cell viability and matrix accumulation, while inflammatory cytokine supplementation had a minor impact. This study demonstrates that intradiscal pH is a dominant factor in determining cell viability and subsequent cell function when compared to physiologically relevant inflammatory conditions. Moreover, we found that NCs allowed for improved cell viability and more effective NP-like matrix synthesis compared to NP cells, and therefore may represent an alternative and appropriate cell choice for disc regeneration.

scholarly journals Both endoplasmic reticulum and mitochondria are involved in disc cell apoptosis and intervertebral disc degeneration in rats

AGE ◽  
2009 ◽  
Vol 32 (2) ◽  
pp. 161-177 ◽  
Author(s):  
Chang-Qing Zhao ◽  
Yue-Hui Zhang ◽  
Sheng-Dan Jiang ◽  
Lei-Sheng Jiang ◽  
Li-Yang Dai
Keyword(s):  
Endoplasmic Reticulum ◽  
Intervertebral Disc ◽  
Disc Degeneration ◽  
Cell Apoptosis ◽  
Intervertebral Disc Degeneration ◽  
Disc Cell
Sign in / Sign up

Export Citation Format

Share Document