scholarly journals Time-Course Changes of Extracellular Matrix Encoding Genes Expression Level in the Spinal Cord Following Contusion Injury—A Data-Driven Approach

2021 ◽  
Vol 22 (4) ◽  
pp. 1744
Author(s):  
Andrea Bighinati ◽  
Zahra Khalajzeyqami ◽  
Vito Antonio Baldassarro ◽  
Luca Lorenzini ◽  
Maura Cescatti ◽  
...  
Keyword(s):  
Gene Expression ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Extracellular Matrix ◽  
Time Course ◽  
Post Injury ◽  
Active Lesion ◽  
Ecm Remodeling ◽  
Cord Injury ◽  
Data Driven Approach

The involvement of the extracellular matrix (ECM) in lesion evolution and functional outcome is well recognized in spinal cord injury. Most attention has been dedicated to the “core” area of the lesion and scar formation, while only scattered reports consider ECM modification based on the temporal evolution and the segments adjacent to the lesion. In this study, we investigated the expression profile of 100 genes encoding for ECM proteins at 1, 8 and 45 days post-injury, in the spinal cord segments rostral and caudal to the lesion and in the scar segment, in a rat model. During both the active lesion phases and the lesion stabilization, we observed an asymmetric gene expression induced by the injury, with a higher regulation in the rostral segment of genes involved in ECM remodeling, adhesion and cell migration. Using bioinformatic approaches, the metalloproteases inhibitor Timp1 and the hyaluronan receptor Cd44 emerged as the hub genes at all post-lesion times. Results from the bioinformatic gene expression analysis were then confirmed at protein level by tissue analysis and by cell culture using primary astrocytes. These results indicated that ECM regulation also takes place outside of the lesion area in spinal cord injury.

scholarly journals PD24-09 POST-INJURY TIME COURSE OF LOWER URINARY TRACT DYSFUNCTION AFTER SPINAL CORD INJURY (SCI) IN THE MOUSE MODEL

2020 ◽  
Vol 203 ◽  
pp. e535-e536
Author(s):  
Tetsuichi Saito* ◽  
Masahiro Kurobe ◽  
Daisuke Gotoh ◽  
Taro Igarashi ◽  
Osamu Ishizuka ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Urinary Tract ◽  
Mouse Model ◽  
Lower Urinary Tract ◽  
Time Course ◽  
Lower Urinary Tract Dysfunction ◽  
Post Injury ◽  
Cord Injury ◽  
Lower Urinary

scholarly journals Cellular response to spinal cord injury in regenerative and non-regenerative stages in Xenopus laevis

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Gabriela Edwards-Faret ◽  
Karina González-Pinto ◽  
Arantxa Cebrián-Silla ◽  
Johany Peñailillo ◽  
José Manuel García-Verdugo ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Extracellular Matrix ◽  
Xenopus Laevis ◽  
Cellular Response ◽  
Central Canal ◽  
Spinal Cord Regeneration ◽  
Post Injury ◽  
Cord Injury ◽  
Regenerative Stage

Abstract Background The efficient regenerative abilities at larvae stages followed by a non-regenerative response after metamorphosis in froglets makes Xenopus an ideal model organism to understand the cellular responses leading to spinal cord regeneration. Methods We compared the cellular response to spinal cord injury between the regenerative and non-regenerative stages of Xenopus laevis. For this analysis, we used electron microscopy, immunofluorescence and histological staining of the extracellular matrix. We generated two transgenic lines: i) the reporter line with the zebrafish GFAP regulatory regions driving the expression of EGFP, and ii) a cell specific inducible ablation line with the same GFAP regulatory regions. In addition, we used FACS to isolate EGFP+ cells for RNAseq analysis. Results In regenerative stage animals, spinal cord regeneration triggers a rapid sealing of the injured stumps, followed by proliferation of cells lining the central canal, and formation of rosette-like structures in the ablation gap. In addition, the central canal is filled by cells with similar morphology to the cells lining the central canal, neurons, axons, and even synaptic structures. Regeneration is almost completed after 20 days post injury. In non-regenerative stage animals, mostly damaged tissue was observed, without clear closure of the stumps. The ablation gap was filled with fibroblast-like cells, and deposition of extracellular matrix components. No reconstruction of the spinal cord was observed even after 40 days post injury. Cellular markers analysis confirmed these histological differences, a transient increase of vimentin, fibronectin and collagen was detected in regenerative stages, contrary to a sustained accumulation of most of these markers, including chondroitin sulfate proteoglycans in the NR-stage. The zebrafish GFAP transgenic line was validated, and we have demonstrated that is a very reliable and new tool to study the role of neural stem progenitor cells (NSPCs). RNASeq of GFAP::EGFP cells has allowed us to clearly demonstrate that indeed these cells are NSPCs. On the contrary, the GFAP::EGFP transgene is mainly expressed in astrocytes in non-regenerative stages. During regenerative stages, spinal cord injury activates proliferation of NSPCs, and we found that are mainly differentiated into neurons and glial cells. Specific ablation of these cells abolished proper regeneration, confirming that NSPCs cells are necessary for functional regeneration of the spinal cord. Conclusions The cellular response to spinal cord injury in regenerative and non-regenerative stages is profoundly different between both stages. A key hallmark of the regenerative response is the activation of NSPCs, which massively proliferate, and are differentiated into neurons to reconstruct the spinal cord. Also very notably, no glial scar formation is observed in regenerative stages, but a transient, glial scar-like structure is formed in non-regenerative stage animals.

scholarly journals Cellular Response to Spinal Cord Injury in Regenerative and Non-Regenerative Stages in Xenopus Laevis

2020 ◽  
Author(s):  
Gabriela Edwards-Faret ◽  
Karina González-Pinto ◽  
Arantxa Cebrián-Silla ◽  
Johany Peñailillo ◽  
José Manuel García-Verdugo ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Extracellular Matrix ◽  
Xenopus Laevis ◽  
Cellular Response ◽  
Central Canal ◽  
Spinal Cord Regeneration ◽  
Post Injury ◽  
Cord Injury ◽  
Regenerative Stage

Abstract Background The efficient regenerative abilities at larvae stages followed by a non-regenerative response after metamorphosis in froglets makes Xenopus an ideal model organism to understand the cellular responses leading to spinal cord regeneration.Methods We compared the cellular response to spinal cord injury between the regenerative and non-regenerative stages of Xenopus laevis. For this analysis, we used electron microscopy, immunofluorescence and histological staining of the extracellular matrix. We generated two transgenic lines: i) the reporter line with the zebrafish GFAP regulatory regions driving the expression of EGFP, and ii) a cell specific inducible ablation line with the same GFAP regulatory regions. In addition, we used FACS to isolate EGFP+ cells for RNAseq analysis.Results In regenerative stage animals, spinal cord regeneration triggers a rapid sealing of the injured stumps, followed by proliferation of cells lining the central canal, and formation of rosette-like structures in the ablation gap. In addition, the central canal is filled by cells with similar morphology to the cells lining the central canal, neurons, axons, and even synaptic structures. Regeneration is almost completed after 20 days post injury. In non-regenerative stage animals, mostly damaged tissue was observed, without clear closure of the stumps. The ablation gap was filled with fibroblast-like cells, and deposition of extracellular matrix components. No reconstruction of the spinal cord was observed even after 40 days post injury. Cellular markers analysis confirmed these histological differences, a transient increase of vimentin, fibronectin and collagen was detected in regenerative stages, contrary to a sustained accumulation of most of these markers, including chondroitin sulfate proteoglycans in the NR-stage. The zebrafish GFAP transgenic line was validated, and we have demonstrated that is a very reliable and new tool to study the role of neural stem progenitor cells (NSPC). RNASeq of GFAP-EGFP cells allowed a clear demonstration that indeed these cells are NSPC. On the contrary, the GFAP-EGFP transgene is mainly expressed in astrocytes in non-regenerative stages. During regenerative stages, spinal cord injury activates proliferation of NSPC, and we found that are mainly fated to form neurons and glial cells. Specific ablation of these cells abolished proper regeneration, confirming that NSPC cells are necessary for functional regeneration of the spinal cord. Conclusions The cellular response to spinal cord injury in regenerative and non-regenerative stages is profoundly different between both stages. A key hallmark of the regenerative response is the activation of NSPC, which massively proliferate to reconstitute the spinal cord, and are differentiated into neurons. Also very notably, no glial scar formation is observed in regenerative stages, but a transient, glial scar-like structure is formed in non-regenerative stage animals.

scholarly journals Transcriptional profiling of non-injured nociceptors after spinal cord injury reveals diverse molecular changes

2019 ◽  
Author(s):  
Jessica R. Yasko ◽  
Isaac L. Moss ◽  
Richard E. Mains
Keyword(s):  
Gene Expression ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Chronic Pain ◽  
Signaling Pathways ◽  
Sensory Neurons ◽  
Traumatic Spinal Cord Injury ◽  
Post Injury ◽  
Inflammatory Signaling ◽  
Cord Injury

AbstractTraumatic spinal cord injury (SCI) has devastating implications for patients, including a high predisposition for developing chronic pain distal to the site of injury. Chronic pain develops weeks to months after injury, consequently patients are treated after irreparable changes have occurred. Nociceptors are central to chronic pain; however, the diversity of this cellular population presents challenges to understanding mechanisms and attributing pain modalities to specific cell types. To begin to address how peripheral sensory neurons distal to the site of injury may contribute to the below-level pain reported by SCI patients, we examined SCI-induced changes in gene expression in lumbar dorsal root ganglia (DRG) below the site of injury. SCI was performed at the T10 vertebral level, with injury produced by a vessel clip with a closing pressure of 15g for 1 minute. Alterations in gene expression produce long-term sensory changes, therefore we were interested in studying SCI-induced transcripts before the onset of chronic pain, which may trigger changes in downstream signaling pathways and ultimately facilitate the transmission of pain. To examine changes in the nociceptor subpopulation in DRG distal to the site of injury, we retrograde labeled sensory neurons projecting to the hairy hindpaw skin with fluorescent dye and collected the corresponding lumbar (L2-L6) DRG 4 days post-injury. Following dissociation, labeled neurons were purified by fluorescence-activated cell sorting. RNA was extracted from sorted sensory neurons of naïve, sham, or SCI mice and sequenced. Transcript abundances validated that the desired population of nociceptors were isolated. Cross-comparisons to data sets from similar studies confirmed we were able to isolate our cells of interest and identify a unique pattern of gene expression within a subpopulation of neurons projecting to the hairy hindpaw skin. Differential gene expression analysis showed high expression levels and significant transcript changes 4 days post-injury in SCI cell populations relevant to the onset of chronic pain. Regulatory interrelationships predicted by pathway analysis implicated changes within the synaptogenesis signaling pathway as well as networks related to inflammatory signaling mechanisms, suggesting a role for synaptic plasticity and a correlation with pro-inflammatory signaling in the transition from acute to chronic pain.Contribution to the fieldTraumatic spinal cord injury (SCI) has devastating implications for patients, including a high predisposition for developing chronic pain. Much of the pain seems to emanate from tissues further away from the brain than the site of injury. Chronic pain develops weeks to months after injury, which means that patients are frequently treated only after enduring pain has developed. Nociceptors are the specialized sensory neurons central to chronic pain. We were interested in studying SCI-induced gene transcript (RNA) changes before the onset of chronic pain, in the hope of identifying mechanisms which could become therapeutic targets. Nociceptors below the site of spinal injury were isolated and their RNAs were sequenced. The results identified a unique pattern of gene expression in the subpopulation of nociceptors projecting to the relevant peripheral tissue. Particularly interesting were sets of genes crucial to synapse formation and maturation – the ability of neurons to talk to each other – and genes involved in inflammatory responses, since treatment of inflammation of nervous tissue could also be important for therapeutic approaches. It is evident that the transition from acute to chronic pain occurs in distinct steps that involve numerous signaling pathways, providing a host of potential new drug targets.

233-LB: Spinal Cord Injury Inhibited-FGF21 Signaling Is Associated with Dysregulation of Metabolic Gene Expression in Mouse Liver and Adipose Tissue

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 233-LB
Author(s):  
XIN-HUA LIU ◽  
LAUREN HARLOW ◽  
ZACHARY GRAHAM ◽  
JOSHUA F. YARROW ◽  
KENNETH CUSI ◽  
...  
Keyword(s):  
Gene Expression ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Adipose Tissue ◽  
Mouse Liver ◽  
Metabolic Gene ◽  
Metabolic Gene Expression ◽  
Cord Injury

scholarly journals D-dopachrome tautomerase activates COX2/PGE2 pathway of astrocytes to mediate inflammation following spinal cord injury

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Huiyuan Ji ◽  
Yuxin Zhang ◽  
Chen Chen ◽  
Hui Li ◽  
Bingqiang He ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Signal Pathways ◽  
Post Injury ◽  
Dopachrome Tautomerase ◽  
Protein Levels ◽  
Cytokines And Chemokines ◽  
Cord Injury ◽  
Mitogen Activated Protein ◽  
Spinal Cord Contusion

Abstract Background Astrocytes are the predominant glial cell type in the central nervous system (CNS) that can secrete various cytokines and chemokines mediating neuropathology in response to danger signals. D-dopachrome tautomerase (D-DT), a newly described cytokine and a close homolog of macrophage migration inhibitory factor (MIF) protein, has been revealed to share an overlapping function with MIF in some ways. However, its cellular distribution pattern and mediated astrocyte neuropathological function in the CNS remain unclear. Methods A contusion model of the rat spinal cord was established. The protein levels of D-DT and PGE2 synthesis-related proteinase were assayed by Western blot and immunohistochemistry. Primary astrocytes were stimulated by different concentrations of D-DT in the presence or absence of various inhibitors to examine relevant signal pathways. The post-injury locomotor functions were assessed using the Basso, Beattie, and Bresnahan (BBB) locomotor scale. Results D-DT was inducibly expressed within astrocytes and neurons, rather than in microglia following spinal cord contusion. D-DT was able to activate the COX2/PGE2 signal pathway of astrocytes through CD74 receptor, and the intracellular activation of mitogen-activated protein kinases (MAPKs) was involved in the regulation of D-DT action. The selective inhibitor of D-DT was efficient in attenuating D-DT-induced astrocyte production of PGE2 following spinal cord injury, which contributed to the improvement of locomotor functions. Conclusion Collectively, these data reveal a novel inflammatory activator of astrocytes following spinal cord injury, which might be beneficial for the development of anti-inflammation drug in neuropathological CNS.

scholarly journals Spinal Cord Injury Increases Pro-inflammatory Cytokine Expression in Kidney at Acute and Sub-chronic Stages

Inflammation ◽  
2021 ◽  
Author(s):  
Shangrila Parvin ◽  
Clintoria R. Williams ◽  
Simone A. Jarrett ◽  
Sandra M. Garraway
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Inflammatory Response ◽  
Inflammatory Cytokine ◽  
Cardiovascular Health ◽  
Mrna Levels ◽  
Post Injury ◽  
Cord Injury ◽  
And Function ◽  
The Impact

Abstract— Accumulating evidence supports that spinal cord injury (SCI) produces robust inflammatory plasticity. We previously showed that the pro-inflammatory cytokine tumor necrosis factor (TNF)α is increased in the spinal cord after SCI. SCI also induces a systemic inflammatory response that can impact peripheral organ functions. The kidney plays an important role in maintaining cardiovascular health. However, SCI-induced inflammatory response in the kidney and the subsequent effect on renal function have not been well characterized. This study investigated the impact of high and low thoracic (T) SCI on C-fos, TNFα, interleukin (IL)-1β, and IL-6 expression in the kidney at acute and sub-chronic timepoints. Adult C57BL/6 mice received a moderate contusion SCI or sham procedures at T4 or T10. Uninjured mice served as naïve controls. mRNA levels of the proinflammatory cytokines IL-1β, IL-6, TNFα, and C-fos, and TNFα and C-fos protein expression were assessed in the kidney and spinal cord 1 day and 14 days post-injury. The mRNA levels of all targets were robustly increased in the kidney and spinal cord, 1 day after both injuries. Whereas IL-6 and TNFα remained elevated in the spinal cord at 14 days after SCI, C-fos, IL-6, and TNFα levels were sustained in the kidney only after T10 SCI. TNFα protein was significantly upregulated in the kidney 1 day after both T4 and T10 SCI. Overall, these results clearly demonstrate that SCI induces robust systemic inflammation that extends to the kidney. Hence, the presence of renal inflammation can substantially impact renal pathophysiology and function after SCI.

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