scholarly journals LRP5-deficiency in OsxCreERT2 mice models intervertebral disc degeneration by aging and compression

2019 ◽  
Author(s):  
Matthew J. Silva ◽  
Nilsson Holguin
Keyword(s):  
Transcription Factor ◽  
Intervertebral Disc ◽  
Wnt Signaling ◽  
Cell Fate ◽  
Biomechanical Properties ◽  
Nucleus Pulposus Cells ◽  
Hypertrophic Chondrocyte ◽  
Age Related ◽  
Ivd Degeneration

ABSTRACTOsterix is a critical transcription factor of mesenchymal stem cell fate, where its loss or loss of WNT signaling diverts differentiation to a chondrocytic lineage. Intervertebral disc (IVD) degeneration activates differentiation of prehypertrophic chondrocyte-like cells and inactivates WNT signaling, but its interacting role with osterix is unclear. First, compared to young-adult (5mo), mechanical compression of old (18mo) IVD induced greater IVD degeneration. Aging (5 vs 12mo) and/or compression reduced the transcription of osterix and notochordal marker T by 40-75%. Compression elevated transcription of hypertrophic chondrocyte marker MMP13 and pre-osterix transcription factor RUNX2, but less so in 12mo IVD. Next, using an Ai9/td reporter and immunohistochemistry, annulus fibrosus and nucleus pulposus cells of 5mo IVD expressed osterix, but aging and compression reduced its expression. Lastly, in vivo LRP5-deficiency in osterix-expressing cells degenerated the IVD, inactivated WNT signaling, reduced the biomechanical properties by 45-70%, and reduced transcription of osterix, notochordal markers and chondrocytic markers by 60-80%. Overall, these data indicate that age-related inactivation of WNT signaling in osterix-expressing cells may limit regeneration by depleting progenitors and attenuating the expansion of chondrocyte-like cells.

Effect of Inflammation on the Osmotic Response of Nucleus Pulposus Cells

2012 ◽  
Author(s):  
Robert Maidhof ◽  
Neena Rajan ◽  
Nadeen O. Chahine
Keyword(s):  
Nucleus Pulposus ◽  
Biomechanical Properties ◽  
Nucleus Pulposus Cells ◽  
Cellular Mechanisms ◽  
Osmotic Response ◽  
Tnf Α ◽  
Disc Cells ◽  
Cytokine Stimulation ◽  
Ivd Degeneration

Intervertebral disc (IVD) degeneration is accompanied by elevated levels of pro-inflammatory cytokines, particularly IL-1β and TNF-α [1]. Disc cells from the nucleus pulposus (NPs) respond to cytokine stimulation with increased catabolic breakdown of the tissue, resulting in a positive feedback of disc integrity loss and further inflammation [2]. Previous studies by our group have examined the response of NP cells to Toll-Like Receptor-4 (TLR-4) activation through stimulation with lipopolysaccharide (LPS). TLR-4 is a pattern recognition receptor that is activated in innate immunity and by polysaccharide fragments from degenerated proteoglycans. TLR-4 activation by LPS results in stimulation of multiple cytokines by NP cells [3]. Moreover, we have shown that in vivo LPS injection results in catabolic changes in the IVD, including matrix breakdown, decrease in biomechanical properties and loss of disc height [4]. However, the specific cellular mechanisms for these catabolic changes remain to be elucidated.

In Vivo Administration of an Inflammatory Stimulant can Trigger Loss of Biomechanical and Biochemical Properties of the Intervertebral Disc

2012 ◽  
Author(s):  
Neena Rajan ◽  
Nate Stetson ◽  
Robert Maidhof ◽  
Mitchell Levine ◽  
Nadeen Chahine
Keyword(s):  
Intervertebral Disc ◽  
Morphological Changes ◽  
Direct Injection ◽  
Biomechanical Properties ◽  
Biochemical Properties ◽  
Post Injury ◽  
Sham Injection ◽  
Tnf Α ◽  
Ivd Degeneration

Human intervertebral disc (IVD) degeneration is accompanied by chronic inflammation, particularly seen in the elevated levels of pro-inflammatory cytokines IL-1β and TNF-α [1–3]. Animal models of disc degeneration (DD) using stab or laceration of the disc generally reproduce morphological changes of IVD degeneration. However, inflammatory changes in these models are thought to be acute and transient post injury [4–6]. The goal of this study is to explore the effect of direct inflammatory stimulation of the IVD on disc biochemical and biomechanical properties in vivo. We utilize lipopolysaccharide (LPS), an inflammatory stimulant that provokes secretion of multiple cytokines by disc cells. We have previously shown that direct injection of LPS into the disc results in significantly higher protein levels of IL-1β, TNF-α, HMGB-1 and MIF vs. sham injection up to 7 days post administration [7]. The goal of this study is to explore the dose-dependent response of this inflammatory stimulation on the biochemical and biomechanical properties of IVD in vivo. We hypothesize that LPS stimulation mimics the pathophysiology of DD by triggering a group of cytokines that are associated with IVD degeneration. LPS is administered using micro needles (<10% disc height) in order to minimize the potential disruption by needle injection.

scholarly journals Retinoic acid inhibits the pyroptosis of degenerated nucleus pulposus cells by activating Sirt1-SOD2 signaling

2021 ◽  
Author(s):  
Peng-Fei Li ◽  
Fei Xiong ◽  
Ying Yin ◽  
Hong-Yuan Xing ◽  
Shao-Jun Hu ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Intervertebral Disc ◽  
Nucleus Pulposus ◽  
Underlying Mechanism ◽  
Ros Generation ◽  
Common Disease ◽  
Nucleus Pulposus Cells ◽  
Ivd Degeneration ◽  
Related Proteins

Abstract Background: Intervertebral disc (IVD) degeneration is a common disease and initiated by the degeneration of nucleus pulposus (NP). The pyroptosis of degenerated NP cells (dNPCs) plays an important role in NP degeneration and may be a potential target in the treatment of IVD degeneration. The purpose of this study is to identify a feasible solution that can inhibit NP cell pyroptosis to therapy the degeneration of the intervertebral disc. Result: In this study, we determined the effects of retinoic acid (RA) on dNPCs and investigated the underlying mechanism of RA mediated pyroptosis in dNPCs. We also verified the effects of RA on IVD degeneration in vivo. Our results demonstrated that RA significantly increased the proliferation and the protein expression of sox9, aggrecan, and collagen II of dNPCs. Pyroptosis-related proteins such as cleaved caspase-1, NT-GSDMD, IL-1β, IL-18, and the pyroptosis rate of dNPCs was significantly decreased by RA. We also found that Sirt1-SOD2 signaling was activated, while ROS generation and TXNIP/NLRP3 signaling in dNPCs was inhibited after the addition of RA. Furthermore, RA also recovered the structure of NP and increased the contents of sGAG and collagen in vivo. Conclusion Our study demonstrated that RA can inhibit the pyroptosis and increase the ECM synthesis function of dNPCs and verified that RA has a protective effect in IVD degeneration.

scholarly journals Caspase-3 knockout inhibits intervertebral disc degeneration related to injury but accelerates degeneration related to aging

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Takashi Ohnishi ◽  
Katsuhisa Yamada ◽  
Koji Iwasaki ◽  
Takeru Tsujimoto ◽  
Hideaki Higashi ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Intervertebral Disc Degeneration ◽  
Caspase 3 ◽  
Treatment Target ◽  
Age Related ◽  
Different Types ◽  
New Treatments ◽  
Surgical Treatments ◽  
Ivd Degeneration ◽  
Primary Effector

AbstractApproximately 40% of people under 30 and over 90% of people 55 or older suffer from moderate-to-severe levels of degenerative intervertebral disc (IVD) disease in their lumbar spines. Surgical treatments are sometimes effective; however, the treatment of back pain related to IVD degeneration is still a challenge; therefore, new treatments are necessary. Apoptosis may be important in IVD degeneration because suppressing cell apoptosis inside the IVD inhibits degeneration. Caspase-3, the primary effector of apoptosis, may be a key treatment target. We analyzed caspase-3’s role in two different types of IVD degeneration using caspase-3 knockout (Casp-3 KO) mice. Casp-3 KO delayed IVD degeneration in the injury-induced model but accelerated it in the age-induced model. Our results suggest that this is due to different pathological mechanisms of these two types of IVD degeneration. Apoptosis was suppressed in the IVD cells of Casp-3 KO mice, but cellular senescence was enhanced. This would explain why the Casp-3 KO was effective against injury-induced, but not age-related, IVD degeneration. Our results suggest that short-term caspase-3 inhibition could be used to treat injury-induced IVD degeneration.

scholarly journals The Wnt signaling pathway effector TCF7L2 is upregulated by insulin and represses hepatic gluconeogenesis

2012 ◽  
Vol 303 (9) ◽  
pp. E1166-E1176 ◽  
Author(s):  
Wilfred Ip ◽  
Weijuan Shao ◽  
Yu-ting Alex Chiang ◽  
Tianru Jin
Keyword(s):  
Gene Expression ◽  
Type 2 Diabetes ◽  
Transcription Factor ◽  
Wnt Signaling ◽  
Wnt Signaling Pathway ◽  
Glucose Production ◽  
Hepatic Gluconeogenesis

Certain single nucleotide polymorphisms (SNPs) in transcription factor 7-like 2 (TCF7L2) are strongly associated with the risk of type 2 diabetes. TCF7L2 and β-catenin (β-cat) form the bipartite transcription factor cat/TCF in stimulating Wnt target gene expression. cat/TCF may also mediate the effect of other signaling cascades, including that of cAMP and insulin in cell-type specific manners. As carriers of TCF7L2 type 2 diabetes risk SNPs demonstrated increased hepatic glucose production, we aimed to determine whether TCF7L2 expression is regulated by nutrient availability and whether TCF7L2 and Wnt regulate hepatic gluconeogenesis. We examined hepatic Wnt activity in the TOPGAL transgenic mouse, assessed hepatic TCF7L2 expression in mice upon feeding, determined the effect of insulin on TCF7L2 expression and β-cat Ser675 phosphorylation, and investigated the effect of Wnt activation and TCF7L2 knockdown on gluconeogenic gene expression and glucose production in hepatocytes. Wnt activity was observed in pericentral hepatocytes in the TOPGAL mouse, whereas TCF7L2 expression was detected in human and mouse hepatocytes. Insulin and feeding stimulated hepatic TCF7L2 expression in vitro and in vivo, respectively. In addition, insulin activated β-cat Ser675 phosphorylation. Wnt activation by intraperitoneal lithium injection repressed hepatic gluconeogenic gene expression in vivo, whereas lithium or Wnt-3a reduced gluconeogenic gene expression and glucose production in hepatic cells in vitro. Small interfering RNA-mediated TCF7L2 knockdown increased glucose production and gluconeogenic gene expression in cultured hepatocytes. These observations suggest that Wnt signaling and TCF7L2 are negative regulators of hepatic gluconeogenesis, and TCF7L2 is among the downstream effectors of insulin in hepatocytes.

Recovery of Intervertebral Disc Degeneration Post Enzymatic Treatment is Mediated by Matrix Metalloproteinases

2011 ◽  
Author(s):  
Nadeen Chahine ◽  
Nate Stetson ◽  
Neena Rajan ◽  
Daniel Grande ◽  
Mitchell Levine
Keyword(s):  
Intervertebral Disc ◽  
Disc Degeneration ◽  
Enzymatic Degradation ◽  
Intervertebral Disc Degeneration ◽  
Biomechanical Properties ◽  
Enzymatic Treatment ◽  
Disc Injury ◽  
Herniated Discs ◽  
Dose Dependent

Enzymatic degradation of the intervertebral disc (IVD) with chondroitinase ABC (ChABC) reduces proteoglycan content of the IVD, thus simulating the GAG loss seen clinically in patients suffering from disc degeneration. This approach has been employed in models of disc injury in rats, rabbits and goats when administered over a large range of dosages [1–3]. Moreover, ChABC has also been used to induce repair of herniated discs in rabbits via chemonucleolysis [4, 5]. Despite the effectiveness of ChABC treatment to reduce the GAG content of the IVD, several recent studies including our own, have shown that this GAG loss is reversible at extended time points post enzymatic treatment [2,6,7]. The goal of the current study is to examine the dose dependent response of IVDs to degradation by ChABC in vivo. We hypothesize that administration of ChABC will result in dose dependent GAG loss and reduced mechanical properties. We administered ChABC at 0.1 U/ml, 1.0 U/ml and 10 U/ml and examined the changes in biomechanical properties, biochemical content, and gene expression in order to examine the biophysical and molecular mechanism by which GAG loss occurs in this model.

scholarly journals Injectable Hydrogel Combined with Nucleus Pulposus-Derived Mesenchymal Stem Cells for the Treatment of Degenerative Intervertebral Disc in Rats

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Feng Wang ◽  
Li-ping Nan ◽  
Shi-feng Zhou ◽  
Yang Liu ◽  
Ze-yu Wang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Intervertebral Disc ◽  
Nucleus Pulposus ◽  
Rat Model ◽  
Injectable Hydrogel ◽  
Cell Scaffold ◽  
Ivd Degeneration

Stem cell-based tissue engineering in treating intervertebral disc (IVD) degeneration is promising. An appropriate cell scaffold can maintain the viability and function of transplanted cells. Injectable hydrogel has the potential to be an appropriate cell scaffold as it can mimic the condition of the natural extracellular matrix (ECM) of nucleus pulposus (NP) and provide binding sites for cells. This study was aimed at investigating the effect of injectable hydrogel-loaded NP-derived mesenchymal stem cells (NPMSC) for the treatment of IVD degeneration (IDD) in rats. In this study, we selected injectable 3D-RGD peptide-modified polysaccharide hydrogel as a cell transplantation scaffold. In vitro, the biocompatibility, microstructure, and induced differentiation effect on NPMSC of the hydrogel were studied. In vivo, the regenerative effect of hydrogel-loaded NPMSC on degenerated NP in a rat model was evaluated. The results showed that NPMSC was biocompatible and able to induce differentiation in hydrogel in vivo. The disc height index (almost 87%) and MRI index (3313.83±227.79) of the hydrogel-loaded NPMSC group were significantly higher than those of other groups at 8 weeks after injection. Histological staining and immunofluorescence showed that the hydrogel-loaded NPMSC also partly restored the structure and ECM content of degenerated NP after 8 weeks. Moreover, the hydrogel could support long-term NPMSC survival and decrease cell apoptosis rate of the rat IVD. In conclusion, injectable hydrogel-loaded NPMSC transplantation can delay the level of IDD and promote the regeneration of the degenerative IVD in the rat model.

Effect of Shear Force on Intervertebral Disc (IVD) Degeneration: An In Vivo Rat Study

2012 ◽  
Vol 40 (9) ◽  
pp. 1996-2004 ◽  
Author(s):  
Jaehyun Kim ◽  
Seok-Jo Yang ◽  
Hyunchul Kim ◽  
Yoonsang Kim ◽  
Joon B. Park ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Shear Force ◽  
Rat Study ◽  
Ivd Degeneration

The SCL Transcription Factor Supports Erythroid Cell Survival and Differentiation Downstream of the Erythropoietin Receptor.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 818-818
Author(s):  
Rachid Lahlil ◽  
Richard Martin ◽  
Peter D. Aplan ◽  
C. Glenn Begley ◽  
Jacqueline E. Damen ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Cell Survival ◽  
Cell Fate ◽  
Genetic Interaction ◽  
Fetal Liver ◽  
Erythropoietin Receptor ◽  
Erythroid Cell ◽  
Loss Of Function

Abstract Erythroid cell development critically depends on the SCL/Tal1 transcription factor and on erythropoietin signalling. In the present study, we have taken several approaches to show that the two genes operate within the same pathway to consolidate the erythroid lineage. Signaling through the erythropoietin receptor (EpoR) upregulates SCL protein levels in a clonal cell line (TF-1) in vitro, and in murine fetal liver cells in vivo, when Epor−/− cells were compared to those of wild type littermates at E12.5. In addition, we provide functional evidence for a linear pathway from EpoR to SCL that regulates erythropoiesis. Interfering with SCL induction or SCL function prevents the anti-apoptotic effect of Epo in TF-1 cells and conversely, ectopic SCL expression is sufficient to substitute for Epo to transiently maintain cell survival. In vivo, SCL gain of function complements the cellular defects in Epor−/− embryos to support cell survival and maturation during primitive and definitive erythropoiesis, as assessed by cellular and histological analyses of Epor−/− SCLtg embryos. Moreover, several erythroid specific genes that are decreased in Epor−/− embryos are rescued by the SCL transgene including glycophorinA, bH1 and bmaj globin, providing molecular confirmation of the functional and genetic interaction between Epor and SCL. Conversely, erythropoiesis becomes deficient in compound Epor+/−SCL+/− heterozygote mice, indicating that the genetic interaction between EpoR and SCL is synthetic. Finally, using EpoR mutants that harbour well defined signalling deficiencies, combined with gain and loss of function approaches for specific kinases, we identify MAPK as the major signal transduction pathway downstream of EpoR that upregulates SCL function, necessary for erythroid cell survival and differentiation. Taken together, our observations are consistent with the view that cytokines can influence cell fate by altering the dosage of lineage transcriptional regulators.

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