JOR SpinePub Date : 2024-01-02DOI: 10.1002/jsp2.1303
Takashi Yurube, William J. Buchser, Zhongying Zhang, Prashanta Silwal, Michael T. Lotze, James D. Kang, Gwendolyn A. Sowa, Nam V. Vo
{"title":"Rapamycin mitigates inflammation-mediated disc matrix homeostatic imbalance by inhibiting mTORC1 and inducing autophagy through Akt activation","authors":"Takashi Yurube, William J. Buchser, Zhongying Zhang, Prashanta Silwal, Michael T. Lotze, James D. Kang, Gwendolyn A. Sowa, Nam V. Vo","doi":"10.1002/jsp2.1303","DOIUrl":"10.1002/jsp2.1303","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Low back pain is a global health problem that originated mainly from intervertebral disc degeneration (IDD). Autophagy, negatively regulated by the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway, prevents metabolic and degenerative diseases by removing and recycling damaged cellular components. Despite growing evidence that autophagy occurs in the intervertebral disc, the regulation of disc cellular autophagy is still poorly understood.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Annulus fibrosus (rAF) cell cultures derived from healthy female rabbit discs were used to test the effect of autophagy inhibition or activation on disc cell fate and matrix homeostasis. Specifically, different chemical inhibitors including rapamycin, 3-methyladenine, MK-2206, and PP242 were used to modulate activities of different proteins in the PI3K/Akt/mTOR signaling pathway to assess IL-1β-induced cellular senescence, apoptosis, and matrix homeostasis in rAF cells grown under nutrient-poor culture condition.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Rapamycin, an inhibitor of mTOR complex 1 (mTORC1), reduced the phosphorylation of mTOR and its effector p70/S6K in rAF cell cultures. Rapamycin also induced autophagic flux as measured by increased expression of key autophagy markers, including LC3 puncta number, LC3-II expression, and cytoplasmic HMGB1 intensity and decreased p62/SQSTM1 expression. As expected, IL-1β stimulation promoted rAF cellular senescence, apoptosis, and matrix homeostatic imbalance with enhanced aggrecanolysis and MMP-3 and MMP-13 expression. Rapamycin treatment effectively mitigated IL-1β-mediated inflammatory stress changes, but these alleviating effects of rapamycin were abrogated by chemical inhibition of Akt and mTOR complex 2 (mTORC2).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These findings suggest that rapamycin blunts adverse effects of inflammation on disc cells by inhibiting mTORC1 to induce autophagy through the PI3K/Akt/mTOR pathway that is dependent on Akt and mTORC2 activities. Hence, our findings identify autophagy, rapamycin, and PI3K/Akt/mTOR signaling as potential therapeutic targets for IDD treatment.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1303","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139390513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-27DOI: 10.1002/jsp2.1307
Maho Koga, Byumsu Kim, Marianne Lintz, Sertaç Kirnaz, Jacob L. Goldberg, Ibrahim Hussain, Branden Medary, Kathleen N. Meyers, Suzanne A. Maher, Roger Härtl, Lawrence J. Bonassar
{"title":"Finite element modeling to predict the influence of anatomic variation and implant placement on performance of biological intervertebral disc implants","authors":"Maho Koga, Byumsu Kim, Marianne Lintz, Sertaç Kirnaz, Jacob L. Goldberg, Ibrahim Hussain, Branden Medary, Kathleen N. Meyers, Suzanne A. Maher, Roger Härtl, Lawrence J. Bonassar","doi":"10.1002/jsp2.1307","DOIUrl":"https://doi.org/10.1002/jsp2.1307","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Tissue-engineered intervertebral disc (TE-IVD) constructs are an attractive therapy for treating degenerative disc disease and have previously been investigated in vivo in both large and small animal models. The mechanical environment of the spine is notably challenging, in part due to its complex anatomy, and implants may require additional mechanical support to avoid failure in the early stages of implantation. As such, the design of suitable support implants requires rigorous validation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We created a FE model to simulate the behavior of the IVD cages under compression specific to the anatomy of the porcine cervical spine, validated the FE model using an animal model, and predicted the effects of implant location and vertebral angle of the motion segment on implant behavior. Specifically, we tested anatomical positioning of the superior vertebra and placement of the implant. We analyzed corresponding stress and strain distributions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Results demonstrated that the anatomical geometry of the porcine cervical spine led to concentrated stress and strain on the posterior side of the cage. This stress concentration was associated with the location of failure of the cages reported in vivo, despite superior mechanical properties of the implant. Furthermore, placement of the cage was found to have profound effects on migration, while the angle of the superior vertebra affected stress concentration of the cage.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This model can be utilized both to inform surgical procedures and provide insight on future cage designs and can be adopted to models without the use of in vivo animal models.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1307","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139047542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-22DOI: 10.1002/jsp2.1311
Chao Song, Daqian Zhou, Kang Cheng, Fei Liu, Weiye Cai, Yongliang Mei, Jingwen Chen, Chenyi Huang, Zongchao Liu
{"title":"Bioinformatics-based discovery of intervertebral disc degeneration biomarkers and immune-inflammatory infiltrates","authors":"Chao Song, Daqian Zhou, Kang Cheng, Fei Liu, Weiye Cai, Yongliang Mei, Jingwen Chen, Chenyi Huang, Zongchao Liu","doi":"10.1002/jsp2.1311","DOIUrl":"10.1002/jsp2.1311","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Intervertebral disc degeneration (IVDD) is a common chronic disease in orthopedics, and its molecular mechanisms are still not well explained.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Aim</h3>\u0000 \u0000 <p>This study's objective was to bioinformatics-based discovery of IVDD biomarkers and immune-inflammatory infiltrates.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and Methods</h3>\u0000 \u0000 <p>The IVDD illness gene collection was gathered from GeneCards, DisGeNet, and gene expression profiles were chosen from the extensive Gene Expression Omnibus database (GSE124272, GSE150408, and GSE153761). The STRING database was used to create a network of protein–protein interactions, while the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases were used for functional enrichment analysis. Using hub genes, the immune cell infiltration between IVDD patient samples and control tissues was examined. Finally, quantitative polymerase chain reaction and Western blot experiments were used to verify the expression of hub genes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of 27 differentially expressed hub genes were identified by bioinformatics. According to GO and KEGG analyses, hub genes were prominent in immunological responses, chemokine-mediated signaling pathways, and inflammatory responses, with the key signaling pathways engaged in cellular senescence, apoptosis, Th1 and Th2 cell differentiation, and Th17 cell differentiation. Immune cell infiltration research revealed that T cells, lymphocytes, B cells, and NK cells were decreased in IVDD patients while monocytes, neutrophils, and CD8 T cells were increased. The expression levels of the senescence hub genes SP1, VEGFA, IL-6, and the apoptosis key gene CASP3 were considerably greater in the IVDD model group than in the control group, according to in vitro validation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>In conclusion, the cellular senescence signaling pathway, the apoptosis signaling pathway, and associated hub genes play significant roles in the development and progression of IVDD, this finding may help direct future research on the senescence signaling route in IVDD.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1311","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138945603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-20DOI: 10.1002/jsp2.1309
Danqing Guo, Min Zeng, Miao Yu, Jingjing Shang, Jinxing Lin, Lichu Liu, Kuangyang Yang, Zhenglin Cao
{"title":"SSR1 and CKAP4 as potential biomarkers for intervertebral disc degeneration based on integrated bioinformatics analysis","authors":"Danqing Guo, Min Zeng, Miao Yu, Jingjing Shang, Jinxing Lin, Lichu Liu, Kuangyang Yang, Zhenglin Cao","doi":"10.1002/jsp2.1309","DOIUrl":"10.1002/jsp2.1309","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Intervertebral disc degeneration (IDD) is a significant cause of low back pain and poses a significant public health concern. Genetic factors play a crucial role in IDD, highlighting the need for a better understanding of the underlying mechanisms.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Aim</h3>\u0000 \u0000 <p>The aim of this study was to identify potential IDD-related biomarkers using a comprehensive bioinformatics approach and validate them in vitro.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and Methods</h3>\u0000 \u0000 <p>In this study, we employed several analytical approaches to identify the key genes involved in IDD. We utilized weighted gene coexpression network analysis (WGCNA), MCODE, LASSO algorithms, and ROC curves to identify the key genes. Additionally, immune infiltrating analysis and a single-cell sequencing dataset were utilized to further explore the characteristics of the key genes. Finally, we conducted in vitro experiments on human disc tissues to validate the significance of these key genes in IDD.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>we obtained gene expression profiles from the GEO database (GSE23130 and GSE15227) and identified 1015 DEGs associated with IDD. Using WGCNA, we identified the blue module as significantly related to IDD. Among the DEGs, we identified 47 hub genes that overlapped with the genes in the blue module, based on criteria of |logFC| ≥ 2.0 and <i>p</i>.adj <0.05. Further analysis using both MCODE and LASSO algorithms enabled us to identify five key genes, of which CKAP4 and SSR1 were validated by GSE70362, demonstrating significant diagnostic value for IDD. Additionally, immune infiltrating analysis revealed that monocytes were significantly correlated with the two key genes. We also analyzed a single-cell sequencing dataset, GSE199866, which showed that both CKAP4 and SSR1 were highly expressed in fibrocartilage chondrocytes. Finally, we validated our findings in vitro by performing real time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) on 30 human disc samples. Our results showed that CKAP4 and SSR1 were upregulated in degenerated disc samples. Taken together, our findings suggest that CKAP4 and SSR1 have the potential to serve as disease biomarkers for IDD.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1309","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138954438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Threats and opportunities of using ChatGPT in scientific writing—The risk of getting spineless","authors":"Luca Ambrosio, Jordy Schol, Vincenzo Amedeo La Pietra, Fabrizio Russo, Gianluca Vadalà, Daisuke Sakai","doi":"10.1002/jsp2.1296","DOIUrl":"10.1002/jsp2.1296","url":null,"abstract":"<p>ChatGPT and AI chatbots are revolutionizing several science fields, including medical writing. However, the inadequate use of such advantageous tools can raise numerous methodological and ethical issues.\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1296","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139004428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-13DOI: 10.1002/jsp2.1310
Xiaolong Chen, Peng Cui, Yongjin Li, Yu Wang, Shibao Lu
{"title":"Links among MRI features in paraspinal muscles, inflammatory processes, and related back pain in patients with lumbar disc herniation","authors":"Xiaolong Chen, Peng Cui, Yongjin Li, Yu Wang, Shibao Lu","doi":"10.1002/jsp2.1310","DOIUrl":"10.1002/jsp2.1310","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Recent studies have provided evidence that structural changes in paraspinal muscles are associated with intervertebral disc degeneration (IDD), ubiquitous with low back pain (LBP), and potentially thought to be regulated by inflammatory processes. However, the links remain unclear.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>The aims of this study were to investigate structural changes in paraspinal muscles that differed in healthy and lumbar disc herniation (LDH) patients, and LDH patients with and without LBP, and to determine the link with the expression of inflammatory marker(s).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Cross-sectional areas (CSAs) and fatty degeneration of muscles were measured in this prospective cohort study. Multifidus muscle (MM) tissue was procured from included individuals undergoing surgery. Gene expression was quantified using qPCR assays. Independent <i>t</i>-test, Chi-square, and Spearman correlation were used for evaluating the links among structural changes, expression of inflammatory markers, and clinical outcomes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Functional CSA and fatty degeneration of MM were larger in healthy group than LDH group. A significant increase in fat infiltration in MM in LBP group than in non-LBP group. TNF-alpha (TNF-α) was 28-fold greater in high-fat infiltration group than low-fat infiltration group within MM. Expression of TNF-α and IL-1β in MM was moderately correlated with functional CSA and fatty degeneration of MM, which was moderately correlated with clinical outcomes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Results support the hypothesis that IDD is associated with dysregulation of inflammatory state of local MM, which provides initial evidence that inflammatory dysregulation in paraspinal muscles has the potential for a broad impact on tissue health and LBP symptoms.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1310","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138976924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-09DOI: 10.1002/jsp2.1299
Hagar M. Kenawy, María I. Nuñez, Xóchitl Morales, Lauren E. Lisiewski, Kevin G. Burt, Min Kyu M. Kim, Leonardo Campos, Nadia Kiridly, Clark T. Hung, Nadeen O. Chahine
{"title":"Sex differences in the biomechanical and biochemical responses of caudal rat intervertebral discs to injury","authors":"Hagar M. Kenawy, María I. Nuñez, Xóchitl Morales, Lauren E. Lisiewski, Kevin G. Burt, Min Kyu M. Kim, Leonardo Campos, Nadia Kiridly, Clark T. Hung, Nadeen O. Chahine","doi":"10.1002/jsp2.1299","DOIUrl":"10.1002/jsp2.1299","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Intervertebral disc degeneration (IDD) is a major cause of low back pain (LBP) worldwide. Sexual dimorphism, or sex-based differences, appear to exist in the severity of LBP. However, it is unknown if there are sex-based differences in the inflammatory, biomechanical, biochemical, and histological responses of intervertebral discs (IVDs).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Caudal (Coccygeal/Co) bone-disc-bone motion segments were isolated from multiple spinal levels (Co8 to Co14) of male and female Sprague–Dawley rats. Changes in motion segment biomechanics and extracellular matrix (ECM) biochemistry (glycosaminoglycan [GAG], collagen [COL], water, and DNA content) were evaluated at baseline and in response to chemical insult (lipopolysaccharide [LPS]) or puncture injury ex vivo. We also investigated the contributions of Toll-like receptor (TLR4) signaling on responses to LPS or puncture injury ex vivo, using a small molecule TLR4 inhibitor, TAK-242.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Findings indicate that IVD motion segments from female donors had greater nitric oxide (NO) release in LPS groups compared to male donors. HMGB1 release was increased in punctured discs, but not LPS injured discs, with no sex effect. Although both male and female discs exhibited reductions in dynamic moduli in response to LPS and puncture injuries, dynamic moduli from female donors were higher than male donors across all groups. In uninjured (baseline) samples, a significant sex effect was observed in nucleus pulposus (NP) DNA and water content. Female annulus fibrosus (AF) also had higher DNA, GAG, and COL content (normalized by dry weight), but lower water content than male AF. Additional injury- and sex-dependent effects were observed in AF GAG/DNA and COL/DNA content. Finally, TAK-242 improved the dynamic modulus of female but not male punctured discs.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our findings demonstrate that there are differences in rat IVD motion segments based on sex, and that the response to injury in inflammatory, biomechanical, biochemical, and histological outcomes also exhibit sex differences. TLR4 inhibition protected against loss of mechanical integrity of puncture-injured IVD motion segments, with differences responses based on donor sex.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1299","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138586052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-04DOI: 10.1002/jsp2.1306
Changli Zhang, Madeleine D. Gordon, Katherine M. Joseph, Martha E. Diaz-Hernandez, Hicham Drissi, Svenja Illien-Jünger
{"title":"Differential efficacy of two small molecule PHLPP inhibitors to promote nucleus Pulposus cell health","authors":"Changli Zhang, Madeleine D. Gordon, Katherine M. Joseph, Martha E. Diaz-Hernandez, Hicham Drissi, Svenja Illien-Jünger","doi":"10.1002/jsp2.1306","DOIUrl":"10.1002/jsp2.1306","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Intervertebral disc (IVD) degeneration is associated with chronic back pain. We previously demonstrated that the phosphatase pleckstrin homology domain and leucine-rich repeat protein phosphatase (PHLPP) 1 was positively correlated with IVD degeneration and its deficiency decelerated IVD degeneration in both mouse IVDs and human nucleus pulposus (NP) cells. Small molecule PHLPP inhibitors may offer a translatable method to alleviate IVD degeneration. In this study, we tested the effectiveness of the two PHLPP inhibitors NSC117079 and NSC45586 in promoting a healthy NP phenotype.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Tail IVDs of 5-month-old wildtype mice were collected and treated with NSC117079 or NSC45586 under low serum conditions ex vivo. Hematoxylin & eosin staining was performed to examine IVD structure and NP cell morphology. The expression of KRT19 was analyzed through immunohistochemistry. Cell apoptosis was assessed by TUNEL assay. Human NP cells were obtained from patients with IVD degeneration. The gene expression of KRT19, ACAN, SOX9, and MMP13 was analyzed via real time qPCR, and AKT phosphorylation and the protein expression of FOXO1 was analyzed via immunoblot.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In a mouse IVD organ culture model, NSC45586, but not NSC117079, preserved vacuolated notochordal cell morphology and KRT19 expression while suppressing cell apoptosis, counteracting the degenerative changes induced by serum deprivation, especially in males. Likewise, in degenerated human NP cells, NSC45586 increased cell viability and the expression of KRT19, ACAN, and SOX9 and reducing the expression of MMP13, while NSC117079 treatment only increased KRT19 expression. Mechanistically, NSC45586 treatment increased FOXO1 protein expression in NP cells, and inhibiting FOXO1 offset NSC45586-induced regenerative potential, especially in males.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our study indicates that NSC45586 was effective in promoting NP cell health, especially in males, suggesting that PHLPP plays a key role in NP cell homeostasis and that NSC45586 might be a potential drug candidate in treating IVD degeneration.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1306","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138602428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-03DOI: 10.1002/jsp2.1298
Jeffrey L. Hutchinson, Matthew A. Veras, Meghan E. Serjeant, Matthew R. McCann, Ashley L. Kelly, Diana Quinonez, Frank Beier, Cheryle A. Séguin
{"title":"Comparative histopathological analysis of age-associated intervertebral disc degeneration in CD-1 and C57BL/6 mice: Anatomical and sex-based differences","authors":"Jeffrey L. Hutchinson, Matthew A. Veras, Meghan E. Serjeant, Matthew R. McCann, Ashley L. Kelly, Diana Quinonez, Frank Beier, Cheryle A. Séguin","doi":"10.1002/jsp2.1298","DOIUrl":"10.1002/jsp2.1298","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Intervertebral disc (IVD) degeneration is a major contributor to back pain and disability. The cause of IVD degeneration is multifactorial, with no disease-modifying treatments. Mouse models are commonly used to study IVD degeneration; however, the effects of anatomical location, strain, and sex on the progression of age-associated degeneration are poorly understood.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A longitudinal study was conducted to characterize age-, anatomical-, and sex-specific differences in IVD degeneration in two commonly used strains of mice, C57BL/6 and CD-1. Histopathological evaluation of the cervical, thoracic, lumbar, and caudal regions of mice at 6, 12, 20, and 24 months of age was conducted by two blinded observers at each IVD for the nucleus pulposus (NP), annulus fibrosus (AF), and the NP/AF boundary compartments, enabling analysis of scores by tissue compartment, summed scores for each IVD, or averaged scores for each anatomical region.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>C57BL/6 mice displayed mild IVD degeneration until 24 months of age; at this point, the lumbar spine demonstrated the most degeneration compared to other regions. Degeneration was detected earlier in the CD-1 mice (20 months of age) in both the thoracic and lumbar spine. In CD-1 mice, moderate to severe degeneration was noted in the cervical spine at all time points assessed. In both strains, age-associated IVD degeneration in the thoracic and lumbar spine was associated with increased histopathological scores in all IVD compartments. In both strains, minimal degeneration was detected in caudal IVDs out to 24 months of age. Both C57BL/6 and CD-1 mice displayed sex-specific differences in the presentation and progression of age-associated IVD degeneration.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These results showed that the progression and severity of age-associated degeneration in mouse models is associated with marked differences based on anatomical region, sex, and strain. This information provides a fundamental baseline characterization for users of mouse models to enable effective and appropriate experimental design, interpretation, and comparison between studies.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1298","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138605130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOR SpinePub Date : 2023-12-01DOI: 10.1002/jsp2.1301
Jessica Ornowski, Lucas Dziesinski, Madeline Hess, Roland Krug, Maryse Fortin, Abel Torres-Espin, Sharmila Majumdar, Valentina Pedoia, Noah B. Bonnheim, Jeannie F. Bailey
{"title":"Thresholding approaches for estimating paraspinal muscle fat infiltration using T1- and T2-weighted MRI: Comparative analysis using water–fat MRI","authors":"Jessica Ornowski, Lucas Dziesinski, Madeline Hess, Roland Krug, Maryse Fortin, Abel Torres-Espin, Sharmila Majumdar, Valentina Pedoia, Noah B. Bonnheim, Jeannie F. Bailey","doi":"10.1002/jsp2.1301","DOIUrl":"10.1002/jsp2.1301","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Paraspinal muscle fat infiltration is associated with spinal degeneration and low back pain, however, quantifying muscle fat using clinical magnetic resonance imaging (MRI) techniques continues to be a challenge. Advanced MRI techniques, including chemical-shift encoding (CSE) based water–fat MRI, enable accurate measurement of muscle fat, but such techniques are not widely available in routine clinical practice.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>To facilitate assessment of paraspinal muscle fat using clinical imaging, we compared four thresholding approaches for estimating muscle fat fraction (FF) using T1- and T2-weighted images, with measurements from water–fat MRI as the ground truth: Gaussian thresholding, Otsu's method, K-mean clustering, and quadratic discriminant analysis. Pearson's correlation coefficients (<i>r</i>), mean absolute errors, and mean bias errors were calculated for FF estimates from T1- and T2-weighted MRI with water–fat MRI for the lumbar multifidus (MF), erector spinae (ES), quadratus lumborum (QL), and psoas (PS), and for all muscles combined.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>We found that for all muscles combined, FF measurements from T1- and T2-weighted images were strongly positively correlated with measurements from the water–fat images for all thresholding techniques (<i>r =</i> 0.70–0.86, <i>p <</i> 0.0001) and that variations in inter-muscle correlation strength were much greater than variations in inter-method correlation strength.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>We conclude that muscle FF can be quantified using thresholded T1- and T2-weighted MRI images with relatively low bias and absolute error in relation to water–fat MRI, particularly in the MF and ES, and the choice of thresholding technique should depend on the muscle and clinical MRI sequence of interest.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14876,"journal":{"name":"JOR Spine","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.1301","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138620759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}