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

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.

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

Current Neurovascular Research ◽

10.2174/1567202616666190906102343 ◽

2019 ◽

Vol 16 (4) ◽

pp. 373-381 ◽

Cited By ~ 1

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.

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A Simple and Cost-Effective Weight Drop Model to Induce Contusive Spinal Cord Injury: Functional and Histological Outcomes

Archives of Neuroscience ◽

10.5812/ans.118775 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Shiva Hashemizadeh ◽

Saereh Hoseindoost ◽

Khalil Pestei ◽

Mahmoudreza Hadjighassem

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Cost Effective ◽

Sensory Function ◽

Therapeutic Interventions ◽

Cord Injury ◽

Male Wistar Rats ◽

Weight Drop ◽

Contusive Spinal Cord Injury ◽

Hind Limb Paralysis

Background: Animal spinal cord injury (SCI) models have provided a better perception of the mechanisms related to traumatic SCI and evaluation of the effectiveness of experimental therapeutic interventions. Objectives: The aim of this study is to develop a cost-effective modified Allen's device to induce contusive spinal cord injury. Methods: Adult male Wistar rats were subjected to contusive spinal cord injury using a customized weight drop model through 10-g weights delivered from a 25-mm height onto an exposed spinal cord. Locomotor and sensory function during 28 days were assessed. Moreover, histopathological changes were assessed at one week and 28 days post SCI. Results: All the SCI rats showed hind limb paralysis up to 48 h post SCI and neuropathic pain after injury. Histological changes similar to the previous reports for contusion model were observed. Conclusions: According to our findings, little variability was observed in the BBB score of individual rats at 28 days after injury. Our customized device to induce spinal cord injury is a simple and inexpensive alternative method to the highly sophisticated contusion device commonly used to induce SCI.

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

Inflammation ◽

10.1007/s10753-021-01507-x ◽

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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Time-dependent progression of neurogenic lower urinary tract dysfunction after spinal cord injury in the mouse model

AJP Renal Physiology ◽

10.1152/ajprenal.00622.2020 ◽

2021 ◽

Author(s):

Tetsuichi Saito ◽

Daisuke Gotoh ◽

Naoki Wada ◽

Pradeep Tyagi ◽

Tomonori Minagawa ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Time Course ◽

Time Dependent ◽

Lower Urinary Tract Dysfunction ◽

Emg Activity ◽

Mrna Levels ◽

Mechanosensitive Channels ◽

Reduction Time ◽

Cord Injury

This study evaluated the time-course changes in bladder and external urinary sphincter (EUS) activity as well as the expression of mechanosensitive channels in lumbosacral dorsal root ganglia (DRG) after spinal cord injury (SCI). Female C57BL/6N mice in the SCI group underwent transection of the Th8/9 spinal cord. Spinal intact mice and SCI mice at 2, 4 and 6 weeks post SCI were evaluated by single-filling cystometry and EUS-electromyography (EMG). In another set of mice, the bladder and L6-S1 DRG were harvested for protein and mRNA analyses. In SCI mice, non-voiding contractions was confirmed at 2 weeks post-SCI, and did not increase over time to 6 weeks. In 2-weeks SCI mice, EUS-EMG measurements revealed detrusor-sphincter dyssynergia (DSD), but periodic EMG reductions during bladder contraction were hardly observed. At 4 weeks, SCI mice showed increases of EMG activity reduction time with increased voiding efficiency (VE). At 6 weeks, SCI mice exhibited a further increase in EMG reduction time. RT-PCR of L6-S1 DRG showed increased mRNA levels of TRPV1 and ASIC1-3 in SCI mice with a decrease of ASIC2-3 at 6 weeks compared to 4 weeks whereas Piezo2 showed a slow increase at 6 weeks. Protein assay showed the SCI-induced overexpression of bladder BDNF with a time-dependent decrease post SCI. These results indicate that detrusor overactivity is established in the early phase whereas DSD is completed later at 4 weeks with an improvement at 6 weeks post SCI, and that mechanosensitive channels may be involved in the time-dependent changes.

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The effect of spinal cord injury on the neurochemical properties of vagal sensory neurons

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00445.2014 ◽

2015 ◽

Vol 308 (12) ◽

pp. R1021-R1033 ◽

Cited By ~ 9

Author(s):

April N. Herrity ◽

Jeffrey C. Petruska ◽

David P. Stirling ◽

Kristofer K. Rau ◽

Charles H. Hubscher

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Vagus Nerve ◽

Sensory Neurons ◽

Receptor Expression ◽

Vagal Afferents ◽

Cord Injury ◽

Male Wistar Rats ◽

Neurochemical Plasticity ◽

Isolectin B4

The vagus nerve is composed primarily of nonmyelinated sensory neurons whose cell bodies are located in the nodose ganglion (NG). The vagus has widespread projections that supply most visceral organs, including the bladder. Because of its nonspinal route, the vagus nerve itself is not directly damaged from spinal cord injury (SCI). Because most viscera, including bladder, are dually innervated by spinal and vagal sensory neurons, an impact of SCI on the sensory component of vagal circuitry may contribute to post-SCI visceral pathologies. To determine whether SCI, in male Wistar rats, might impact neurochemical characteristics of NG neurons, immunohistochemical assessments were performed for P2X3 receptor expression, isolectin B4 (IB4) binding, and substance P expression, three known injury-responsive markers in sensory neuronal subpopulations. In addition to examining the overall population of NG neurons, those innervating the urinary bladder also were assessed separately. All three of the molecular markers were represented in the NG from noninjured animals, with the majority of the neurons binding IB4. In the chronically injured rats, there was a significant increase in the number of NG neurons expressing P2X3 and a significant decrease in the number binding IB4 compared with noninjured animals, a finding that held true also for the bladder-innervating population. Overall, these results indicate that vagal afferents, including those innervating the bladder, display neurochemical plasticity post-SCI that may have implications for visceral homeostatic mechanisms and nociceptive signaling.

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Ultrastructural scoring of graded acute spinal cord injury in the rat

Journal of Neurosurgery Spine ◽

10.3171/spi.2002.97.1.0049 ◽

2002 ◽

Vol 97 (1) ◽

pp. 49-56 ◽

Cited By ~ 9

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.

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A reproducible spinal cord injury model in the cat

Journal of Neurosurgery ◽

10.3171/jns.1983.59.2.0268 ◽

1983 ◽

Vol 59 (2) ◽

pp. 268-275 ◽

Cited By ~ 53

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.

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

BioMed Research International ◽

10.1155/2020/5615097 ◽

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.

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Catalpol Protects Against Spinal Cord Injury in Mice Through Regulating MicroRNA-142-Mediated HMGB1/TLR4/NF-κB Signaling Pathway

Frontiers in Pharmacology ◽

10.3389/fphar.2020.630222 ◽

2021 ◽

Vol 11 ◽

Author(s):

Hougang Xia ◽

Dandan Wang ◽

Xiaohui Guo ◽

Kaidi Wu ◽

Fuwei Huang ◽

...

Keyword(s):

Oxidative Stress ◽

Spinal Cord ◽

Spinal Cord Injury ◽

Inflammatory Response ◽

Inflammatory Factors ◽

Tunel Staining ◽

Ros Generation ◽

Bv2 Cells ◽

Cord Injury ◽

Oxidative Response

Background: Spinal cord injury (SCI) is a devastating condition that leads to paralysis, disability and even death in severe cases. Inflammation, apoptosis and oxidative stress in neurons are key pathogenic processes in SCI. Catalpol (CTP), an iridoid glycoside extracted from Rehmannia glutinosa, has many pharmacological activities, such as anti-inflammatory, anti-oxidative and anti-apoptotic properties.Purpose: Here, we investigated whether CTP could exert neuroprotective effects against SCI, and explored the underlying mechanism involved.Methods: SCI was induced by a weight-drop device and treated with CTP (10 mg and 60 mg/kg). Then the locomotor function of SCI mice was evaluated by the BBB scores, spinal cord edema was measured by the wet/dry weight method, oxidative stress markers and inflammatory factors were detected by commercial kits and neuronal death was measured by TUNEL staining. Moreover, the microRNA expression profile in spinal cords from mice following SCI was analyzed using miRNA microarray. In addition, reactive oxygen species (ROS) generation, inflammatory response and cell apoptosis were detected in murine microglia BV2 cells under oxygen-glucose deprivation (OGD) and CTPtreatment.Results: Our data showed that CTP treatment could improve the functional recovery, as well as suppress the apoptosis, alleviate inflammatory and oxidative response in SCI mice. In addition, CTP was found to be up-regulated miR-142 and the protective effects of CTP on apoptosis, inflammatory and oxidative response may relate to its regulation of HMGB1/TLR4/NF-κB pathway through miR-142.Conclusion: Our findings suggest that CTP may protect the spinal cord from SCI by suppression of apoptosis, oxidative stress and inflammatory response via miR-142/HMGB1/TLR4/NF-κB pathway.

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Effects of chronic spinal cord injury on relationships among ion channel and receptor mRNAs in mouse lumbar spinal cord

10.1101/357665 ◽

2018 ◽

Cited By ~ 1

Author(s):

Virginia B. Garcia ◽

Matthew D. Abbinanti ◽

Ronald M. Harris-Warrick ◽

David J. Schulz

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Ion Channel ◽

Motor Neurons ◽

Receptor Expression ◽

Lumbar Spinal Cord ◽

Mrna Levels ◽

Absolute Quantitation ◽

Cord Injury ◽

Lumbar Spinal

ABSTRACTSpinal cord injury (SCI) causes widespread changes in gene expression of the spinal cord, even in the undamaged spinal cord below the level of the lesion. Less is known about changes in the correlated expression of genes after SCI. We investigated gene co-expression networks among voltage-gated ion channel and neurotransmitter receptor mRNA levels using quantitative RT-PCR in longitudinal slices of the mouse lumbar spinal cord in control and chronic SCI animals. These longitudinal slices were made from the ventral surface of the cord, thus forming slices relatively enriched in motor neurons or interneurons. We performed absolute quantitation of mRNA copy number for 50 ion channel or receptor transcripts from each sample, and used multiple correlation analyses to detect patterns in correlated mRNA levels across all pairs of genes. The majority of channels and receptors changed in expression as a result of chronic SCI, but did so differently across slice levels. Furthermore, motor neuron enriched slices experienced an overall loss of correlated channel and receptor expression, while interneuron slices showed a dramatic increase in the number of positively correlated transcripts. These correlation profiles suggest that spinal cord injury induces distinct changes across cell types in the organization of gene co-expression networks for ion channels and transmitter receptors.

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