scholarly journals mir-21a-5p promote the progress of inflammation after Traumatic Spinal Cord Injury via up-regulating neurotoxic reactive astrocyte (A1) polarization by inhibiting CNTF/STAT3/Nkrf pathway

2020 ◽  
Author(s):  
Yining Zhang ◽  
Tingting Meng ◽  
Jianan Chen ◽  
Ying Zhang ◽  
Jianning Kang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Reactive Astrocytes ◽  
Luciferase Reporter ◽  
Chip Assay ◽  
Qrt Pcr ◽  
Pulldown Assay ◽  
Cord Injury

Abstract Background Reactive astrocytes play an important role in Traumatic Spinal Cord Injury (TSCI). Interestingly, naive astrocytes can easily transform into neurotoxic reactive astrocytes(A1s) when inflammatory stimulation occurs. Previous researches have reported that miR-21a-5p is involved in the regulation of various stages of Spinal Cord Injury (SCI). However, it is not clear whether miR-21a-5p affected the polarization of reactive astrocytes. The purpose of our study was to detect the effects and mechanism of miR-21a-5p in the induction of neurotoxic reactive astrocytes (A1s) formation. Methods Gene chip assay and qRT-PCR were used to detect the expression of Cntfr α in TSCI models or sham operation. Bioinformatics analysis was used to speculate the potential targeting of miR-21a-5p, which was further confirmed by qRT-PCR, western blotting, a dual-luciferase reporter assay, and RNA pulldown assay. In vivo, the TSCI model was performed by a 68099Ⅱ precision percussion device, and the A1s phenotype was identified by immunofluorescence staining. In vitro, A1s were induced by IL-1 α, TNF-α, and C1q. A1s and neuroprotective reactive astrocytes (A2s) markers were confirmed by qRT-PCR, western blotting, and immunofluorescence. ChIP assay was used to explore the targeting gene of STAT3, the downstream of Cntfr α. Results The expression of miR-21a-5p was significantly increased while Cntfr α was decreased since naive astrocytes transformed into A1s after 3 days post-TSCI. In addition, the mRNA and protein of Cntfr α were decreased while miR-21a-5p was overexpressed. The binding site between miR-21a-5p and Cntfr α was further confirmed by the dual-luciferase reporter and RNA pulldown assay. We also discovered that A1s markers were decreased while markers of A2s were increased with the pretreatment of CNTF. Chromatin immunoprecipitation (ChIP) assay was used to prove that CNTF inhibited A1s induction by activating the expression of Nkrf via the CNTF/STAT3 pathway. Downregulation of miR-21a-5p enhanced the inhibitory effect of CNTF in A1s in vitro. In vivo, the expression of A1s markers significantly decreased with the treatment of antagomir-21, while Cntfr α siRNA treatment was just the opposite. Conclusion We observed that increased miR-21a-5p down-regulated Cntfr α in A1s induced by TSCI, promoting the inflammatory process. In addition, we also identified the effect and potential mechanism of CNTF, a specific ligand of CNTFR α, on inhibiting naive astrocytes transformed into A1s for the first time. Collectively, our studies demonstrated that targeting miR-21a-5p is a prospective therapy for curing TSCI.

scholarly journals Quercetin prevents necroptosis of oligodendrocytes by inhibiting macrophages/microglia polarization to M1 phenotype after spinal cord injury in rats

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Hong Fan ◽  
Hai-Bin Tang ◽  
Le-Qun Shan ◽  
Shi-Chang Liu ◽  
Da-Geng Huang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
M1 Macrophages ◽  
Qrt Pcr ◽  
Cord Injury ◽  
Microglia Polarization ◽  
M1 Phenotype ◽  
Quercetin Treatment

Abstract Background Oligodendrocytes (OLs) death after spinal cord injury (SCI) contributes to demyelination, even leading to a permanent neurological deficit. Besides apoptosis, our previous study demonstrated that OLs underwent receptor-interacting serine-threonine kinase 3(RIP3)/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis. Considering that necroptosis is always accompanied with pro-inflammatory response and quercetin has long been used as anti-inflammatory agent, in the present study we investigated whether quercetin could inhibit necroptosis of OLs and suppress the M1 macrophages/microglia-mediated immune response after SCI as well as the possible mechanism. Methods In this study, we applied quercetin, an important flavonoid component of various herbs, to treat rats with SCI and rats injected with saline were employed as the control group. Locomotor functional recovery was evaluated using Basso-Beattie-Bresnahan (BBB) scoring and rump-height Index (RHI) assay. In vivo, the necroptosis, apoptosis, and regeneration of OLs were detected by immunohistochemistry, 5′-bromo-2′-deoxyuridine (BrdU) incorporation. The loss of myelin and axons after SCI were evaluated by Luxol fast blue (LFB) staining, immunohistochemistry, and electron microscopic study. The polarization of macrophages/microglia after SCI and the underlying mechanisms were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. In vitro, the ATP and reactive oxygen species (ROS) level examination, propidium iodide (PI) labeling, and Western blotting were used to analyze the necroptosis of cultured OLs, while the signaling pathways-mediated polarization of cultured macrophages/microglia was detected by qRT-PCR and Western blotting. Results We demonstrated that quercetin treatment improved functional recovery in rats after SCI. We then found that quercetin significantly reduced necroptosis of OLs after SCI without influencing apoptosis and regeneration of OLs. Meanwhile, myelin loss and axon loss were also significantly reduced in quercetin-treated rats, as compared to SCI + saline control. Further, we revealed that quercetin could suppress macrophages/microglia polarized to M1 phenotype through inhibition of STAT1 and NF-κB pathway in vivo and in vitro, which contributes to the decreased necroptosis of OLs. Conclusions Quercetin treatment alleviated necroptosis of OLs partially by inhibiting M1 macrophages/microglia polarization after SCI. Our findings suggest that necroptosis of OLs may be a potential therapeutic target for clinical SCI.

scholarly journals A Collagen-Based Scaffold for Promoting Neural Plasticity in a Rat Model of Spinal Cord Injury

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2245
Author(s):  
Jue-Zong Yeh ◽  
Ding-Han Wang ◽  
Juin-Hong Cherng ◽  
Yi-Wen Wang ◽  
Gang-Yi Fan ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Rat Model ◽  
Neural Plasticity ◽  
Collagen Scaffold ◽  
Glial Scar ◽  
Beneficial Effects ◽  
Cord Injury

In spinal cord injury (SCI) therapy, glial scarring formed by activated astrocytes is a primary problem that needs to be solved to enhance axonal regeneration. In this study, we developed and used a collagen scaffold for glial scar replacement to create an appropriate environment in an SCI rat model and determined whether neural plasticity can be manipulated using this approach. We used four experimental groups, as follows: SCI-collagen scaffold, SCI control, normal spinal cord-collagen scaffold, and normal control. The collagen scaffold showed excellent in vitro and in vivo biocompatibility. Immunofluorescence staining revealed increased expression of neurofilament and fibronectin and reduced expression of glial fibrillary acidic protein and anti-chondroitin sulfate in the collagen scaffold-treated SCI rats at 1 and 4 weeks post-implantation compared with that in untreated SCI control. This indicates that the collagen scaffold implantation promoted neuronal survival and axonal growth within the injured site and prevented glial scar formation by controlling astrocyte production for their normal functioning. Our study highlights the feasibility of using the collagen scaffold in SCI repair. The collagen scaffold was found to exert beneficial effects on neuronal activity and may help in manipulating synaptic plasticity, implying its great potential for clinical application in SCI.

scholarly journals Immunosuppressants Affect Human Neural Stem Cells In Vitro but Not in an In Vivo Model of Spinal Cord Injury

2013 ◽  
Vol 2 (10) ◽  
pp. 731-744 ◽  
Author(s):  
Christopher J. Sontag ◽  
Hal X. Nguyen ◽  
Noriko Kamei ◽  
Nobuko Uchida ◽  
Aileen J. Anderson ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Stem Cells ◽  
Spinal Cord Injury ◽  
Neural Stem Cells ◽  
In Vivo Model ◽  
Human Neural Stem Cells ◽  
Cord Injury

scholarly journals Depolarization and electrical stimulation enhance in vitro and in vivo sensory axon growth after spinal cord injury

2018 ◽  
Vol 300 ◽  
pp. 247-258 ◽  
Author(s):  
Ioana Goganau ◽  
Beatrice Sandner ◽  
Norbert Weidner ◽  
Karim Fouad ◽  
Armin Blesch
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Electrical Stimulation ◽  
Axon Growth ◽  
Sensory Axon ◽  
Cord Injury

scholarly journals miRNA-544a Regulates the Inflammation of Spinal Cord Injury by Inhibiting the Expression of NEUROD4

2018 ◽  
Vol 51 (4) ◽  
pp. 1921-1931 ◽  
Author(s):  
Lei Yang ◽  
Dawei Ge ◽  
Xi Chen ◽  
Chunzhi Jiang ◽  
Shengnai Zheng
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Grip Strength ◽  
Target Gene ◽  
Interleukin 1 ◽  
Luciferase Reporter ◽  
Interleukin 17 ◽  
Qrt Pcr ◽  
Gene Assay ◽  
Cord Injury

Background/Aims: To explore the potential role of miR-544a in spinal cord injury and the possible mechanism involved. Methods: We established a mouse model with spinal cord injury to examine the changes in grip force recovery of the forelimb or the posterior limb of the mouse. Microarray was performed to achieve differentiated miRNAs in the mice. The expressions of miR-544a, MCP-1, IL36B and IL17B after spinal cord injury were detected by qRT-PCR. Subsequently, miR-544a was overexpressed to observe changes in inflammation and grip strength after spinal cord injury. Target gene of miR-544a was then predicted using bioinformatics technology. Finally, dual luciferase reporter gene assay was used to verify the binding of miR-544a to its target gene. Results: Using mice models with spinal cord injury, we found that the strength of their four limbs began to recover 7 days after injury. The results of microarray and qRT-PCR confirmed that mir-544a level in mice with spinal cord injury decreased with increase of injury time, while the levels of inflammatory genes MCP-1 (monocyte chemoattractant protein-1), IL1 (interleukin-1) and TNF-α (tumor necrosis factor alpha) IL36B (interleukin-36 beta) and IL17B (interleukin-17 beta) were significantly increased. However, overexpression of miR-544a in the mice significantly reduced the level of inflammation and restored their grip strength in their four limbs. Finally, we found that miR-544a can bind to the NEUROD4 (Neurogenic differentiation 4) 3’UTR (Untranslated Region) region through bioinformatics website prediction, which was further confirmed by dual luciferase reporter assay. NEUROD4 level was significantly reduced following the overexpression of miR-544a. Conclusion: The expression of miR-544a was significantly decreased after spinal cord injury. High expression of miR-544a could alleviate the inflammation caused by spinal cord injury and promote the recovery of spinal cord via the inhibition of NEUROD4.

scholarly journals Cytokine and Growth Factor Activation In Vivo and In Vitro after Spinal Cord Injury

2016 ◽  
Vol 2016 ◽  
pp. 1-21 ◽  
Author(s):  
Elisa Garcia ◽  
Jorge Aguilar-Cevallos ◽  
Raul Silva-Garcia ◽  
Antonio Ibarra
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Critical Role ◽  
Glutamate Excitotoxicity ◽  
Signaling Proteins ◽  
Neurodegenerative Process ◽  
Cord Injury ◽  
Ion Imbalance

Spinal cord injury results in a life-disrupting series of deleterious interconnected mechanisms encompassed by the primary and secondary injury. These events are mediated by the upregulation of genes with roles in inflammation, transcription, and signaling proteins. In particular, cytokines and growth factors are signaling proteins that have important roles in the pathophysiology of SCI. The balance between the proinflammatory and anti-inflammatory effects of these molecules plays a critical role in the progression and outcome of the lesion. The excessive inflammatory Th1 and Th17 phenotypes observed after SCI tilt the scale towards a proinflammatory environment, which exacerbates the deleterious mechanisms present after the injury. These mechanisms include the disruption of the spinal cord blood barrier, edema and ion imbalance, in particular intracellular calcium and sodium concentrations, glutamate excitotoxicity, free radicals, and the inflammatory response contributing to the neurodegenerative process which is characterized by demyelination and apoptosis of neuronal tissue.

scholarly journals Docosahexaenoic Acid-Loaded Polylactic Acid Core-Shell Nanofiber Membranes for Regenerative Medicine after Spinal Cord Injury: In Vitro and In Vivo Study

2020 ◽  
Vol 21 (19) ◽  
pp. 7031
Author(s):  
Zhuo-Hao Liu ◽  
Yin-Cheng Huang ◽  
Chang-Yi Kuo ◽  
Chao-Ying Kuo ◽  
Chieh-Yu Chin ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Docosahexaenoic Acid ◽  
Neurite Outgrowth ◽  
Polylactic Acid ◽  
In Vivo Study ◽  
Core Shell ◽  
Cord Injury

Spinal cord injury (SCI) is associated with disability and a drastic decrease in quality of life for affected individuals. Previous studies support the idea that docosahexaenoic acid (DHA)-based pharmacological approach is a promising therapeutic strategy for the management of acute SCI. We postulated that a nanostructured material for controlled delivery of DHA at the lesion site may be well suited for this purpose. Toward this end, we prepare drug-loaded fibrous mats made of core-shell nanofibers by electrospinning, which contained a polylactic acid (PLA) shell for encapsulation of DHA within the core, for delivery of DHA in situ. In vitro study confirmed sustained DHA release from PLA/DHA core-shell nanofiber membrane (CSNM) for up to 36 days, which could significantly increase neurite outgrowth from primary cortical neurons in 3 days. This is supported by the upregulation of brain-derived neurotropic factor (BDNF) and neurotrophin-3 (NT-3) neural marker genes from qRT-PCR analysis. Most importantly, the sustained release of DHA could significantly increase the neurite outgrowth length from cortical neuron cells in 7 days when co-cultured with PLA/DHA CSNM, compared with cells cultured with 3 μM DHA. From in vivo study with a SCI model created in rats, implantation of PLA/DHA CSNM could significantly improve neurological functions revealed by behavior assessment in comparison with the control (no treatment) and the PLA CSNM groups. According to histological analysis, PLA/DHA CSNM also effectively reduced neuron loss and increased serotonergic nerve sprouting. Taken together, the PLA/DHA CSNM may provide a nanostructured drug delivery system for DHA and contribute to neuroprotection and promoting neuroplasticity change following SCI.

scholarly journals Alterations of protein composition along the rostro-caudal axis after spinal cord injury: proteomic, in vitro and in vivo analyses

2014 ◽  
Vol 8 ◽  
Author(s):  
Dasa Cizkova ◽  
Françoise Le Marrec-Croq ◽  
Julien Franck ◽  
Lucia Slovinska ◽  
Ivana Grulova ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Protein Composition ◽  
Cord Injury

scholarly journals VDAC1 is essential for neurite maintenance and the inhibition of its oligomerization protects spinal cord from demyelination and facilitates locomotor function recovery after spinal cord injury

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Vera Paschon ◽  
Beatriz Cintra Morena ◽  
Felipe Fernandes Correia ◽  
Giovanna Rossi Beltrame ◽  
Gustavo Bispo dos Santos ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Cell Death ◽  
Conformational Changes ◽  
Secondary Response ◽  
Disulfonic Acid ◽  
Function Recovery ◽  
Cord Injury

Abstract During the progression of the neurodegenerative process, mitochondria participates in several intercellular signaling pathways. Voltage-dependent anion-selective channel 1 (VDAC1) is a mitochondrial porin involved in the cellular metabolism and apoptosis intrinsic pathway in many neuropathological processes. In spinal cord injury (SCI), after the primary cell death, a secondary response that comprises the release of pro-inflammatory molecules triggers apoptosis, inflammation, and demyelination, often leading to the loss of motor functions. Here, we investigated the functional role of VDAC1 in the neurodegeneration triggered by SCI. We first determined that in vitro targeted ablation of VDAC1 by specific morpholino antisense nucleotides (MOs) clearly promotes neurite retraction, whereas a pharmacological blocker of VDAC1 oligomerization (4, 4′-diisothiocyanatostilbene-2, 2′-disulfonic acid, DIDS), does not cause this effect. We next determined that, after SCI, VDAC1 undergoes conformational changes, including oligomerization and N-terminal exposition, which are important steps in the triggering of apoptotic signaling. Considering this, we investigated the effects of DIDS in vivo application after SCI. Interestingly, blockade of VDAC1 oligomerization decreases the number of apoptotic cells without interfering in the neuroinflammatory response. DIDS attenuates the massive oligodendrocyte cell death, subserving undisputable motor function recovery. Taken together, our results suggest that the prevention of VDAC1 oligomerization might be beneficial for the clinical treatment of SCI.

scholarly journals Molecular Mechanism of MiR-136-5p Targeting NF-κB/A20 in the IL-17-Mediated Inflammatory Response after Spinal Cord Injury

2017 ◽  
Vol 44 (3) ◽  
pp. 1224-1241 ◽  
Author(s):  
Jichen He ◽  
Jinmin Zhao ◽  
Xiaoming Peng ◽  
Xiongzhi Shi ◽  
Shaohui Zong ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Inflammatory Factors ◽  
Scoring Method ◽  
Histological Changes ◽  
Cord Injury ◽  
Rat Astrocytes ◽  
Underlying Mechanisms

Background/Aims: The pathophysiology of spinal cord injury (SCI) results in serious damage to the human body via an increase in the secondary biological processes imposed by activated astrocytes. Abnormal expression of microRNAs after SCI has become a potential research focus. However, the underlying mechanisms are poorly understood. Methods: SCI models were established in rats using Allen’s method, and the BBB scoring method was employed to assess locomotor function. Lentivirus was used to infect rat astrocytes and SCI rats. Real-time PCR and antibody chip were used to measure gene expression and cytokine secretion. Western blot analysis was employed to detect protein expression. HE staining was used to assess the histological changes in SCI. The immunohistochemical staining of A20 and p-NF-κB in SCI was also analyzed. Results: The in vitro experiment showed that miR-136-5p up-regulated the expression of p-NF-κB by down-regulating the expression of A20 so that astrocytes produced inflammatory factors and chemokines. The in vivo experiment indicated that overexpressed miR-136-5p promoted the production of inflammatory factors, chemokines and p-NF-κB in SCI rats, whereas it inhibited the expression of A20 protein and increased inflammatory cell infiltration and injuries in the spinal cord. Conclusion: The current findings indicate that silencing miR-136-5p effectively decreased inflammatory factors and chemokines and protected the spinal cord via NF-κB/A20 signaling in vivo and in vitro. In contrast, overexpression of miR-136-5p had the opposite effect.

Sign in / Sign up

Export Citation Format

Share Document