MiR-34a Inhibits Spinal Cord Injury and Blocks Spinal Cord Neuron Apoptosis by Activating Phatidylinositol 3-kinase (PI3K)/AKT Pathway Through Targeting CD47

2019 ◽  
Vol 16 (4) ◽  
pp. 373-381 ◽  
Author(s):  
Liao Qi ◽  
Ming Jiang-Hua ◽  
Hu Ge-Liang ◽  
Chen Qing ◽  
Li Ya-Ming
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Rating Scale ◽  
Akt Pathway ◽  
Spinal Neuron ◽  
Tunel Staining ◽  
Cord Injury ◽  
Weight Drop ◽  
Related Proteins ◽  
Neuron Apoptosis

Objective: Dysregulation of miR-34a has been reported for its implication in neuronal development. This study aims to explore the effect and possible mechanism of miR-34a on neuron apoptosis induced by Spinal Cord Injury (SCI). Materials and Methods: SCI model was established using Allen's weight-drop method and rats in the sham group were performed with laminectomy without weight-drop injury. Basso Bcattie Bresnahan (BBB) rating scale was applied to evaluate the locomotor function of rats. Pathological changes of spinal cord tissues in SCI rats were observed after hematoxylin and eosin (HE) staining. Rats were separately injected with miR-34a agomir, miR-34a agomir NC, si-CD47 and si- CD47 NC before their spinal cord tissues were collected for terminal-deoxynucleoitidyl Transferase Mediated nick end labeling (TUNEL) staining. Expressions of miR-34a, si-CD47, apoptosis related proteins and AKT pathway related proteins were measured by quantitative reverse transcription- polymerase chain reaction (qRT-PCR) and western blot. Results: SCI rat models were successfully established evidenced by decreased BBB scores and HE staining. Injection of miR-34a agomir and/or si-CD47 could suppress neuron cell apoptosis, with deceased apoptotic index (AI) and pro-apoptotic protein (cleaved caspase-3 and Bax) levels, and increased expressions of anti-apoptotic proteins (Bcl-2 and Mcl-1). Phosphorylated levels of phatidylinositol 3-kinase (PI3K) and AKT were further increased in rats injected with miR-34a agomir and si-CD47, compared with miR-34a agomir or si-CD47 injection alone. Conclusion: MiR-34a can downregulate CD47 expression to activate PI3K/AKT signal pathway, and thus inhibit SCI induced spinal neuron apoptosis.

scholarly journals Exosomes Derived from Nerve Stem Cells Loaded with FTY720 Promote the Recovery after Spinal Cord Injury in Rats by PTEN/AKT Signal Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Jianbin Chen ◽  
Can Zhang ◽  
Shouye Li ◽  
Zheming Li ◽  
Xiaojing Lai ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Stem Cells ◽  
Spinal Cord Injury ◽  
Akt Pathway ◽  
Tunel Staining ◽  
Sprague Dawley ◽  
Inflammatory Infiltration ◽  
Cord Injury ◽  
Related Proteins

Background. Spinal cord injury (SCI) remains a challenge owing to limited therapies. The exosome of neural stem cells (NSCs-Exos) and FTY720 transplantation could improve SCI effectively. However, the effect and mechanism of NSCs-Exos combined with FTY720 (FTY720-NSCs-Exos) transplantation in the treatment of SCI are not fully understood. Methods. Sprague Dawley rats (8-week-old) were used to establish the SCI model, followed by the treatment of NSCs-Exos, FTY720, and FTY720-NSCs-Exos. The effect of FTY720, NSCs-Exos, and FTY720-NSCs-Exos combination treatment on hindlimb function, pathological changes, apoptosis activity, and the expression of spinal edema-related proteins and apoptosis-related proteins in SCI models were investigated by BBB scoring, HE staining, TUNEL staining and immunohistochemistry, and Western blotting. Meanwhile, the effect of these treatments on spinal cord microvascular endothelial cells (SCMECs) was detected under hypoxic circumstance. Results. Our results found that FTY720-NSCs-Exos could alleviate pathological alterations and ameliorate the hindlimb function and oxygen insufficiency in model mice after SCI. In addition, exosomes could ameliorate the morphology of neurons, reduce inflammatory infiltration and edema, decrease the expression of Bax and AQP-4, upregulate the expression of claudin-5 and Bcl-2, and inhibit cell apoptosis. At the same time, in vitro experiments showed that FTY720-NSCs-Exos could protect the barrier of SCMECs under hypoxic circumstance, and the mechanism is related to PTEN/AKT pathway. Conclusion. FTY720-NSCs-Exos therapy displayed a positive therapeutic effect on SCI by regulating PTEN/AKT pathway and offered a new therapy for SCI.

scholarly journals Extracellular vesicles derived from mesenchymal stem cells containing microRNA-381 protect against spinal cord injury in a rat model via the BRD4/WNT5A axis

2021 ◽  
Vol 10 (5) ◽  
pp. 328-339
Author(s):  
Xufeng Jia ◽  
Guangping Huang ◽  
Shaohua Wang ◽  
Miao Long ◽  
Xiaojun Tang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Stem Cells ◽  
Spinal Cord Injury ◽  
Mesenchymal Stem Cells ◽  
Extracellular Vesicles ◽  
Rat Model ◽  
Luciferase Assay ◽  
Tunel Staining ◽  
Cord Injury ◽  
Neuron Apoptosis

Aims Non-coding microRNA (miRNA) in extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) may promote neuronal repair after spinal cord injury (SCI). In this paper we report on the effects of MSC-EV-microRNA-381 (miR-381) in a rodent model of SCI. Methods In the current study, the luciferase assay confirmed a binding site of bromodomain-containing protein 4 (BRD4) and Wnt family member 5A (WNT5A). Then we detected expression of miR-381, BRD4, and WNT5A in dorsal root ganglia (DRG) cells treated with MSC-isolated EVs and measured neuron apoptosis in culture by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. A rat model of SCI was established to detect the in vivo effect of miR-381 and MSC-EVs on SCI. Results We confirmed an interaction between miR-381 and BRD4, and showed that miR-381 overexpression inhibited the expression of BRD4 in DRG cells as well as the apoptosis of DRG cells through WNT5A via activation of Ras homologous A (RhoA)/Rho-kinase activity. Moreover, treatment of MSC-EVs rescued neuron apoptosis and promoted the recovery of SCI through inhibition of the BRD4/WNT5A axis. Conclusion Taken altogether, miR-381 derived from MSC-EVs can promote the recovery of SCI through BRD4/WNT5A axis, providing a new perspective on SCI treatment. Cite this article: Bone Joint Res 2021;10(5):328–339.

scholarly journals Involvement of Asc and Nlrp3 inflammasomes in the testes following spinal cord injury

2020 ◽  
Vol 54 (2) ◽  
pp. 96-108
Author(s):  
Hajar Ramezanikhah ◽  
Ahmad Farrokhi ◽  
Reza Nejatbakhsh ◽  
Saeed Shokri ◽  
Adib Zendedel ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Germ Cells ◽  
Seminiferous Tubules ◽  
Tunel Staining ◽  
Mrna Levels ◽  
Male Subfertility ◽  
Cord Injury ◽  
Male Wistar Rats ◽  
Weight Drop

AbstractObjective. The exact mechanism, by which spinal cord injury (SCI) leads to a male subfertility is not well-known. Present study was conducted to determine the mechanisms that lead to the elevated end-product cytokines and inflammasomes in the testes of an SCI rat model. Moreover, we evaluated the inflammasome components following SCI in testis over a defined time periods.Methods. Weight drop technique was used to induce SCI at the level of the T10 vertebra in male Wistar rats. The animals were sacrificed at specific time intervals (3, 7, 14, 21, and 28 day’s post-SCI). mRNA levels of inflammasomes and cytokines were measured by real-time PCR, germ cells apoptosis was evaluated by TUNEL staining, and the epithelium of seminiferous tubules by Miller’s and Johnsen’s scores.Results. The results showed activation of Nlrp3 in the testes of SCI animals at different time points. Expression of Nlrp3 and IL-1β sharply increased 14 days after the SCI. Upregulation of IL-1β and IL-18 at days 14 and 21 post-SCI might disintegrate the epithelium of seminiferous tubules at day 14 and induce germ cells apoptosis, increase abnormal sperm cells, and attenuate motility and viability at 21 days post-SCI.Conclusion. This study provided further evidence of innate immunity activation in testes that could lead to more disruption of spermatogenesis in SCI patients at specific times.

The role of multiple hyperbaric oxygenation in expanding therapeutic windows after acute spinal cord injury in rats

2003 ◽  
Vol 99 (2) ◽  
pp. 198-205 ◽  
Author(s):  
Lixin Huang ◽  
Maheshkumar P. Mehta ◽  
Anil Nanda ◽  
John H. Zhang
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Hyperbaric Oxygenation ◽  
Rating Scale ◽  
Therapeutic Window ◽  
Content Type ◽  
Cord Injury ◽  
Weight Drop ◽  
Fine Print

Object. Hyperbaric oxygenation (HBO) therapy has been reported to improve neurological recovery after spinal cord injury (SCI). In the present study, the authors examined whether multiple HBO therapy can expand the therapeutic window after acute SCI. Methods. Seventy rats were randomly assigned to seven groups: sham surgery; SCI without treatment; single HBO treatment beginning at 30 minutes, 3 hours, and 6 hours after SCI; and multiple HBO treatments starting at 6 and 24 hours postinjury. Mild SCI was induced by adjusting the height of a weight drop (10 g) to 6.25 mm above the exposed spinal cord. A single HBO administration was performed at 2.82 ata for 1 hour. The multiple HBO treatment modality was performed once daily for 1 week. All rats underwent behavioral testing with the Basso-Beattie-Breshnahan locomotor rating scale twice a week. Rats were killed on Day 42 postinjury and specimens comprising the lesioned area were histopathologically examined. Those rats that received single HBO intervention beginning at 30 minutes and 3 hours and those that received multiple HBO treatment starting at 6 hours following injury made significantly greater neurological recoveries than those in the nontreatment SCI group. These rats also retained more sparing tissue than controls. Conclusions. The results of this study demonstrate that multiple HBO treatments can expand the therapeutic window for acute SCI to 6 hours after injury.

Ultrastructural scoring of graded acute spinal cord injury in the rat

2002 ◽  
Vol 97 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Erkan Kaptanoglu ◽  
Selcuk Palaoglu ◽  
H. Selcuk Surucu ◽  
Mutlu Hayran ◽  
Etem Beskonakli
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Behavioral Assessment ◽  
Traumatic Injury ◽  
Significant Negative Correlation ◽  
Content Type ◽  
Cord Injury ◽  
Contusion Injury ◽  
Weight Drop ◽  
Fine Print

Object. There is a need for an accurate quantitative histological technique that also provides information on neurons, axons, vascular endothelium, and subcellular organelles after spinal cord injury (SCI). In this paper the authors describe an objective, quantifiable technique for determining the severity of SCI. The usefulness of ultrastructural scoring of acute SCI was assessed in a rat model of contusion injury. Methods. Spinal cords underwent acute contusion injury by using varying weights to produce graded SCI. Adult Wistar rats were divided into five groups. In the first group control animals underwent laminectomy only, after which nontraumatized spinal cord samples were obtained 8 hours postsurgery. The weight-drop technique was used to produce 10-, 25-, 50-, and 100-g/cm injuries. Spinal cord samples were also obtained in the different trauma groups 8 hours after injury. Behavioral assessment and ultrastructural evaluation were performed in all groups. When the intensity of the traumatic injury was increased, behavioral responses showed a decreasing trend. A similar significant negative correlation was observed between trauma-related intensity and ultrastructural scores. Conclusions. In the present study the authors characterize quantitative ultrastructural scoring of SCI in the acute, early postinjury period. Analysis of these results suggests that this method is useful in evaluating the degree of trauma and the effectiveness of pharmacotherapy in neuroprotection studies.

A reproducible spinal cord injury model in the cat

1983 ◽  
Vol 59 (2) ◽  
pp. 268-275 ◽  
Author(s):  
Ronald W. J. Ford
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Spinal Cord Injuries ◽  
Sharp Transition ◽  
Content Type ◽  
Spinal Cord Injury Model ◽  
Injury Model ◽  
Cord Injury ◽  
Weight Drop ◽  
Future Evaluation

✓ Allen's weight-drop method for producing experimental spinal cord injuries was improved by placing a curved stainless steel plate anterior to the spinal cord to provide a smooth, hard surface for the receipt of posterior cord impact. In addition, an electronic circuit was used to ensure that cord injury was produced by a single impact, thereby enhancing the reproducibility of the injury mechanism. Using a spinal cord injury model with these modifications, the author found that the recovery of hindlimb function and the histopathological appearance of the injured cord 6 weeks after upper lumbar injury were closely related to injury magnitude. The curve of functional recovery versus injury magnitude has a sharp transition centered at 10 gm × 15 cm, and indicates that an injury of 10 gm × 20 cm produces a “threshold” lesion suitable for the future evaluation of spinal cord treatment methods.

Activation of SIRT1 by Hyperbaric  Oxygenation Promotes Recovery of Motor Dysfunction in Spinal Cord Injury Rats

2020 ◽  
Author(s):  
Huiqiang Chen ◽  
Mengyu Yao ◽  
Zhibo Li ◽  
Ranran Xing ◽  
Cheng Zhang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Molecular Mechanisms ◽  
Hyperbaric Oxygenation ◽  
Rating Scale ◽  
Motor Dysfunction ◽  
Sprague Dawley ◽  
Inflammatory Cascade ◽  
Locomotor Function ◽  
Cord Injury

Abstract Background: Emerging evidence demonstrated that hyperbaric oxygenation (HBO) therapy improved the locomotor dysfunction following spinal cord injury (SCI). Sirtuin1(SIRT1) has been characterized as neuroprotection in nerve system. However, whether SIRT1 is involved in alleviation of locomotor function by HBO therapy is unclear. Methods: The Basso, Beattie Bresnahan (BBB) locomotor rating scale was used to evaluate the open-field locomotor function. Western blot, real-time quantitative reverse transcription polymerase chain reaction, SIRT1 activity assay and enzyme-linked immunosorbent assays were performed to explore the molecular mechanisms in adult Sprague-Dawley rats. Results: We found that series HBO therapy significantly improved the locomotor dysfunction and ameliorated the decrease mRNA, protein and activity of spinal cord SIRT1 induced by traumatic SCI injury in rats. In addition, intraperitoneal injection SIRT1 antagonist EX-527 abolished the beneficial effects of series HBO treatment on locomotor deficits and SIRT1 activity loss caused by traumatic SCI injury. However, the rats undergone both series HBO therapy and SIRT1 agonist SRT1720 got the higher BBB score than that undergone series HBO treatment only. Importantly, series HBO treatment following the traumatic SCI injury inhibited the inflammatory cascade and apoptosis-related protein, which was retained by EX-527 and enhanced by SRT1720. Furthermore, EX-527 blocked the enhanced induction of autophagy series with HBO application. Conclusion: These findings demonstrated a new mechanism for series HBO therapy involving activation of SIRT1 and subsequent modulation of inflammatory cascade, apoptosis and autophagy, which contributed to the recovery of motor dysfunction. Key words: HBO, SIRT1, motor dysfunction, inflammation, autophagy, apoptosis

scholarly journals Reducing Neuron Apoptosis in the Pontine Micturition Center by Nerve Root Transfer for Restoration of Micturition Function after Spinal Cord Injury

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Ronghua Yu ◽  
Gang Yin ◽  
Jianguo Zhao ◽  
Huihao Chen ◽  
Depeng Meng ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Nerve Root ◽  
Neuronal Apoptosis ◽  
Nerve Transfer ◽  
Tunel Staining ◽  
Nerve Roots ◽  
Cord Injury ◽  
Group A ◽  
Group B

Objective. The rate of neuronal apoptosis increases after spinal cord injury (SCI). Anastomosing the normal nerve roots above the SCI level to the injured sacral nerve roots can enhance the functional recovery of neurons. Therefore, we evaluated the effect of sacral nerve root transfer after SCI on pontine neuronal survival. Methods. Sprague–Dawley rats were randomly divided into three groups: Group A, reconstruction of afferent and efferent nerve pathways of the bladder after SCI; Group B, SCI only; and Group C, control group. We examined pontine neuronal morphology using hematoxylin and eosin (H&E) staining after SCI and nerve transfer. Bcl-2 and Bax protein expression changes in the pontine micturition center were quantified by immunohistochemistry. The number of apoptotic neurons was determined by TUNEL staining. We examined pontine neuronal apoptosis by transmission electron microscopy (TEM) at different time points. Results. H&E staining demonstrated that the number of neurons had increased in Group A, but more cells in Group B displayed nuclear pyknosis, with the disappearance of the nucleus. Compared with Group B, Group A had significantly higher Bcl-2 expression, significantly lower Bax expression, and a significantly higher Bcl-2/Bax ratio. The number of apoptotic neurons and neuron bodies in Group A was significantly lower than that in Group B, as indicated by TUNEL staining and TEM. Conclusions. These findings demonstrate that lumbosacral nerve transfer can reduce neuronal apoptosis in the pontine micturition center and enhance functional recovery of neurons. This result further suggests that lumbosacral nerve transfer can be used as a new approach for reconstructing bladder function after spinal cord injury.

scholarly journals Early CSF Biomarkers and Late Functional Outcomes in Spinal Cord Injury. A Pilot Study

2020 ◽  
Vol 21 (23) ◽  
pp. 9037
Author(s):  
Rita Capirossi ◽  
Beatrice Piunti ◽  
Mercedes Fernández ◽  
Elisa Maietti ◽  
Paola Rucci ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Injury Severity ◽  
Rating Scale ◽  
Treatment Effectiveness ◽  
Neurological Diseases ◽  
Csf Biomarkers ◽  
Clinical Scores ◽  
Cord Injury ◽  
Scale Scores

Although, biomarkers are regarded as an important tool for monitoring injury severity and treatment efficacy, and for predicting clinical evolution in many neurological diseases and disorders including spinal cord injury, there is still a lack of reliable biomarkers for the assessment of clinical course and patient outcome. In this study, a biological dataset of 60 cytokines/chemokines, growth factorsm and intracellular and extracellular matrix proteins, analyzed in CSF within 24 h of injury, was used for correlation analysis with the clinical dataset of the same patients. A heat map was generated of positive and negative correlations between biomarkers and clinical rating scale scores at discharge, and between biomarkers and changes in clinical scores during the observation period. Using very stringent statistical criteria, we found 10 molecules which correlated with clinical scores at discharge, and five molecules, which correlated with changes in clinical scores. The proposed methodology may be useful for generating hypotheses regarding “predictive” and “treatment effectiveness” biomarkers, thereby suggesting potential candidates for disease-modifying therapies using a “bed-to-bench” approach.

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