Proteome profiling of spinal cord and dorsal root ganglia in rats with trinitrobenzene sulfonic acid-induced colitis

AIM: To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: The colonic myeloperoxidase (MPO) activity and tumor necrosis factor-(TNF- ) level were determined. A two-dimensional electrophoresis (2-DE)-based proteomic technique was used to profile the global protein expression changes in the DRG and spinal cord of the rats with acute colitis induced by intracolonic injection of TNBS. RESULTS: TNBS group showed significantly elevated colonic MPO activity and increased TNF-level. The proteins derived from lumbosacral enlargement of the spinal cord and DRG were resolved by 2-DE; and 26 and 19 proteins that displayed significantly different expression levels in the DRG and spinal cord were identified respectively. Altered proteins were found to be involved in a number of biological functions, such as inflammation/immunity, cell signaling, redox regulation, sulfate transport and cellular metabolism. The over-expression of the protein similar to potassium channel tetramerisation domain containing protein 12 (Kctd 12) and low expression of proteasome subunit type-1 (psma) were validated by Western blotting analysis. CONCLUSION: TNBS-induced colitis has a profound impact on protein profiling in the nervous system. This result helps understand the neurological pathogenesis of inflammatory bowel disease.

Effects of intrathecal injection of glial cell inhibitor on spinal cord astrocytes following chronic compression of dorsal root ganglia in rats

BACKGROUND： Astrocytes are considered to provide nutritional support in the central nervous system. However, recent studies have confirmed that astrocytes also play an important role in chronic pain. OBJECTIVE： To investigate the effects of intrathecal injection of fluorocitrate, minocycline or both on astrocyte activation and proliferation in the spinal dorsal horn of compressed dorsal root ganglion in rats. DESIGN, TIME AND SETTING： The neurology randomized controlled animal study was performed at the Jiangsu Institute of Anesthesia Medicine, from September 2006 to April 2007. MATERIALS： A total of 96 male Sprague Dawley rats, aged 6-8 weeks, were selected for this study. Following intrathecal catheterization, 80 rats underwent steel bar insertion into the L4-5 intervertebral foramina to make a stable compression on the L4-5 posterior root ganglion. Thus rat models of ganglion compression were established. Minocycline and fluorocitrate were purchased from Sigma, USA. METHODS： A total of 96 rats were randomly and equally divided into six groups. Rat L4, L5 transverse process and intervertebral foramina were exposed in the sham operation group, but without steel bar insertion. The model group did not receive any manipulations. Rats in the phosphate buffered saline （PBS） group were intrathecally injected with 0.01 mmol/L PBS （20 μL）. Rats in the fluorocitrate group were subjected to 1 μmol/L fluorocitrate （20 μL）. Rats in the minocycline group were intrathecally injected with 5 g/L minocycline （20 μL）. Rats in the minocycline and fluorocitrate group received a mixture （20 μL） of 5 g/L minocycline and 1 μmol/L fluorocitrate. Following model establishment, drugs were administered once a day. MAIN OUTCOME MEASURES： At 7 and 14 days following model induction, glial fibrillary acidic protein expression in the spinal dorsal horn was measured by immunofluorescence microscopy. Six sections with significant glial fibrillary acidic protein -positive expression were obtained to count astrocytes under an inverted microscope. RESULTS： No significant differences in astrocyte count were detected between the fluorocitrate and model groups. Cell bodies were small with a few processes in the fluorocitrate group, compared with the model group. The astrocyte count decreased significantly in the minocycline group and the minocycline and fluorocitrate group compared with the sham operation, model, PBS and fluorocitrate groups （P 〈 0.01）. The decrease in astrocyte count was mainly found in layers Ⅲ–Ⅳ of the spinal dorsal horn. Cell body volume was smaller and process numbers were fewer in the minocycline group and the minocycline and fluorocitrate group, compared with the model and PBS groups. CONCLUSION： Fluorocitrate can inhibit astrocyte activation, but does not affect astrocyte proliferation. However, minocycline can inhibit the activation and proliferation of astrocytes.

BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies.

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoration of the injured spinal cord.

Satellite glial cells in sensory ganglia play a wider role in chronic pain via multiple mechanisms

Satellite glial cells are unique glial cells that surround the cell body of primary sensory neurons.An increasing body of evidence suggests that in the presence of inflammation and nerve damage,a significant number of satellite glial cells become activated,thus triggering a series of functional changes.This suggests that satellite glial cells are closely related to the occurrence of chronic pain.In this review,we first summarize the morphological structure,molecular markers,and physiological functions of satellite glial cells.Then,we clarify the multiple key roles of satellite glial cells in chronic pain,including gap junction hemichannel Cx43,membrane channel Pannexin1,K channel subunit 4.1,ATP,purinergic P2 receptors,and a series of additional factors and their receptors,including tumor necrosis factor,glutamate,endothelin,and bradykinin.Finally,we propose that future research should focus on the specific sorting of satellite glial cells,and identify genomic differences between physiological and pathological conditions.This review provides an important perspective for clarifying mechanisms underlying the peripheral regulation of chronic pain and will facilitate the formulation of new treatment plans for chronic pain.

Laser speckle contrast imaging to predict the effect of temporary spinal cord stimulation in postherpetic neuralgia patients: A prospective observational study

Temporary spinal cord stimulation(tSCS)can effectively reduce the pain and severity of postherpetic neuralgia(PHN).However,there are no effective and objective methods for predicting the effects of tSCS on PHN.Laser speckle contrast imaging(LSCI)is frequently used in neurology to evaluate the effectiveness of treatment.To assess the accuracy of LSCI in predicting the impact of tSCS on PHN,14 adult patients receiving tSCS treatments for spinal nerve-innervated(C6-T2)PHN participated in this observational study.Visual analog scale(VAS)assessments and LSCI bloodflow images of the-ngers were recorded after the tSCS procedure.The results showed that the VAS scores of all patients decreased signi-cantly.Moreover,the bloodflow index(BFI)values were signi-cantly higher than they were before the procedure.Increased bloodflow and pain alleviation were positively correlated.The-ndings indicated that spinal nerve PHN(C6-T2)was signi-cantly reduced by tSCS.Pain alleviation by tSCS was positively correlated with increased bloodflow in the hand.The effect of tSCS on PHN may thus be predicted using an independent and consistent indicator such as LSCI.

Surgical intervention combined with weight-bearing walking training promotes recovery in patients with chronic spinal cord injury:a randomized controlled study

For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.

Epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China:a hospital-based retrospective study

Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.

Steel bar penetrating cervical spinal canal without neurological injury:A case report

BACKGROUND We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures.CASE SUMMARY A 58-year-old male patient was admitted to the emergency department with a steel bar penetrating the neck,without signs of neurological deficit.Computed tomography(CT)demonstrated that the steel bar had penetrated the cervical spinal canal at the C6–7 level,causing C6 and C7 vertebral body fracture,C6 left lamina fracture,left facet joint fracture,and penetration of the cervical spinal cord.The steel bar was successfully removed through an open surgical procedure by a multidisciplinary team.During the surgery,we found that the cervical vertebra,cervical spinal canal and cervical spinal cord were all severely injured.Postoperative CT demonstrated severe penetration of the cervical spinal canal but the patient returned to a fully functional level without any neurological deficits.CONCLUSION Even with a serious cervical spinal canal penetrating trauma,the patient could resume normal work and life after appropriate treatment.

Reduction of epinephrine in the lumbar spinal cord following repetitive blast-induced traumatic brain injury in rats

Traumatic brain inju ry-induced unfavorable outcomes in human patients have independently been associated with dysregulated levels of monoamines,especially epinephrine,although few preclinical studies have examined the epinephrine level in the central nervous system after traumatic brain injury.Epinephrine has been shown to regulate the activities of spinal motoneurons as well as increase the heart rate,blood pressure,and blood flow to the hindlimb muscles.Therefore,the purpose of the present study was to determine the impact of repeated blast-induced traumatic brain injury on the epinephrine levels in seve ral function-s pecific central nervous system regions in rats.Following three repeated blast injuries at 3-day intervals,the hippocampus,motor cortex,locus coeruleus,vestibular nuclei,and lumbar spinal cord were harvested at post-injury day eight and processed for epinephrine assays using a high-sensitive electrochemical detector cou pled with high-performance liquid chromatography.Our results showed that the epinephrine levels were significantly decreased in the lumbar spinal cord tissues of blast-induced traumatic brain injury animals compared to the levels detected in age-and sex-matched sham controls.In other function-specific central nervous system regions,although the epinephrine levels were slightly altered following blast-induced tra u matic brain injury,they were not statistically significant.These results suggest that blast injury-induced significant downregulation of epinephrine in the lumbar spinal cord could negatively impact the motor and cardiovascular function.This is the first repo rt to show altered epinephrine levels in the spinal cord following repetitive mild blast-induced traumatic brain injury.

Analgesic Effect of Combined Spinal-Epidural Anesthesia and its Effect on TNF-α and CRP Levels in Elderly Patients with Hip Fracture During Surgical Treatment

Objective:To observe the analgesic effect of combined spinal and epidural anesthesia on older patients undergoing hip fracture surgery.Method:One hundred and twenty elderly hip fracture surgery patients treated in our hospital from January 2021 to December 2022 were selected and randomly divided into two groups,with 60 cases in the experimental group and 60 in the control group.The experimental group was given combined spinal-epidural anesthesia intervention measures,while the control group was given epidural anesthesia intervention measures.The analgesic effect,tumor necrosis factor-alpha(TNF-α),C-reactive protein(CRP)levels,and other observation indicators were analyzed after anesthesia intervention.Result:After the intervention,the analgesic effect and the evaluation results of the subjects in the experimental group were better than those in the control group(P<0.05);the obtained values of TNF-αand CRP levels in the experimental group were higher than those of the control group(P<0.05).Conclusion:The combined spinal-epidural anesthesia intervention demonstrated positive outcomes.The analgesic effect of patients during surgery and their inflammatory factor levels improved,which makes this intervention worthy of clinical application and promotion.

The future of artificial hibernation medicine:protection of nerves and organs after spinal cord injury

Spinal cord injury is a serious disease of the central nervous system involving irreversible nerve injury and various organ system injuries.At present,no effective clinical treatment exists.As one of the artificial hibernation techniques,mild hypothermia has preliminarily confirmed its clinical effect on spinal cord injury.However,its technical defects and barriers,along with serious clinical side effects,restrict its clinical application for spinal cord injury.Artificial hibernation is a futureoriented disruptive technology for human life support.It involves endogenous hibernation inducers and hibernation-related central neuromodulation that activate particular neurons,reduce the central constant temperature setting point,disrupt the normal constant body temperature,make the body adapt"to the external cold environment,and reduce the physiological resistance to cold stimulation.Thus,studying the artificial hibernation mechanism may help develop new treatment strategies more suitable for clinical use than the cooling method of mild hypothermia technology.This review introduces artificial hibernation technologies,including mild hypothermia technology,hibernation inducers,and hibernation-related central neuromodulation technology.It summarizes the relevant research on hypothermia and hibernation for organ and nerve protection.These studies show that artificial hibernation technologies have therapeutic significance on nerve injury after spinal co rd injury through inflammatory inhibition,immunosuppression,oxidative defense,and possible central protection.It also promotes the repair and protection of res pirato ry and digestive,cardiovascular,locomoto r,urinary,and endocrine systems.This review provides new insights for the clinical treatment of nerve and multiple organ protection after spinal cord injury thanks to artificial hibernation.At present,artificial hibernation technology is not mature,and research fa ces various challenges.Neve rtheless,the effort is wo rthwhile for the future development of medicine.

Photobiomodulation inhibits the expression of chondroitin sulfate proteoglycans after spinal cord injury via the Sox9 pathway

Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins such as chondroitin sulfate proteoglycans inside and around the glial scar is known to affect axonal growth and be a major obstacle to autogenous repair.These proteins are thus candidate targets for spinal cord injury therapy.Our previous studies demonstrated that 810 nm photo biomodulation inhibited the formation of chondroitin sulfate proteoglycans after spinal cord injury and greatly improved motor function in model animals.However,the specific mechanism and potential targets involved remain to be clarified.In this study,to investigate the therapeutic effect of photo biomodulation,we established a mouse model of spinal cord injury by T9 clamping and irradiated the injury site at a power density of 50 mW/cm~2 for 50 minutes once a day for 7 consecutive days.We found that photobiomodulation greatly restored motor function in mice and down regulated chondroitin sulfate proteoglycan expression in the injured spinal cord.Bioinformatics analysis revealed that photobiomodulation inhibited the expression of proteoglycan-related genes induced by spinal cord injury,and versican,a type of proteoglycan,was one of the most markedly changed molecules.Immunofluorescence staining showed that after spinal cord injury,versican was present in astrocytes in spinal cord tissue.The expression of versican in primary astrocytes cultured in vitro increased after inflammation induction,whereas photobiomodulation inhibited the expression of ve rsican.Furthermore,we found that the increased levels of p-Smad3,p-P38 and p-Erk in inflammatory astrocytes were reduced after photobiomodulation treatment and after delivery of inhibitors including FR 180204,(E)-SIS3,and SB 202190.This suggests that Sma d 3/Sox9 and MAP K/Sox9 pathways may be involved in the effects of photobiomodulation.In summary,our findings show that photobiomodulation modulates the expression of chondroitin sulfate proteoglycans,and versican is one of the key target molecules of photo biomodulation.MAPK/Sox9 and Smad3/Sox9 pathways may play a role in the effects of photo biomodulation on chondroitin sulfate proteoglycan accumulation after spinal cord injury.

The MORC2 p.S87L mutation reduces proliferation of pluripotent stem cells derived from a patient with the spinal muscular atrophy-like phenotype by inhibiting proliferation-related signaling pathways

Mutations in the microrchidia CW-type zinc finger protein 2(MORC2)gene are the causative agent of Charcot-Marie-Tooth disease type 2Z(CMT2Z),and the hotspot mutation p.S87L is associated with a more seve re spinal muscular atrophy-like clinical phenotype.The aims of this study were to determine the mechanism of the severe phenotype caused by the MORC2 p.S87L mutation and to explore potential treatment strategies.Epithelial cells were isolated from urine samples from a spinal muscular atrophy(SMA)-like patient[MORC2 p.S87L),a CMT2Z patient[MORC2 p.Q400R),and a healthy control and induced to generate pluripotent stem cells,which were then differentiated into motor neuron precursor cells.Next-generation RNA sequencing followed by KEGG pathway enrichment analysis revealed that differentially expressed genes involved in the PI3K/Akt and MAP K/ERK signaling pathways were enriched in the p.S87L SMA-like patient group and were significantly downregulated in induced pluripotent stem cells.Reduced proliferation was observed in the induced pluripotent stem cells and motor neuron precursor cells derived from the p.S87L SMA-like patient group compared with the CMT2Z patient group and the healthy control.G0/G1 phase cell cycle arrest was observed in induced pluripotent stem cells derived from the p.S87L SMA-like patient.MORC2 p.S87Lspecific antisense oligonucleotides(p.S87L-ASO-targeting)showed significant efficacy in improving cell prolife ration and activating the PI3K/Akt and MAP K/ERK pathways in induced pluripotent stem cells.Howeve r,p.S87L-ASO-ta rgeting did not rescue prolife ration of motor neuron precursor cells.These findings suggest that downregulation of the PI3K/Akt and MAP K/ERK signaling pathways leading to reduced cell proliferation and G0/G1 phase cell cycle arrest in induced pluripotent stem cells might be the underlying mechanism of the severe p.S87L SMA-like phenotype.p.S87L-ASO-targeting treatment can alleviate disordered cell proliferation in the early stage of pluripotent stem cell induction.

Progress in the generation of spinal cord organoids over the past decade and future perspectives

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in vivo.As emerging bioengineering methods have led to the optimization of cell culture protocols,spinal cord organoids technology has made remarkable advancements in the past decade.Our literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal axes.Moreover,fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional assessment.These qualities make spinal cord organoids valuable tools for disease modeling,drug screening,and tissue regeneration.By utilizing this emergent technology,researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord diseases.However,at present,spinal cord organoid technology remains in its infancy and has not been widely applied in translational medicine.Establishment of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

Bromocriptine protects perilesional spinal cord neurons from lipotoxicity after spinal cord injury

Recent studies have revealed that lipid droplets accumulate in neurons after brain injury and evoke lipotoxicity,damaging the neurons.However,how lipids are metabolized by spinal cord neurons after spinal cord injury remains unclear.Herein,we investigated lipid metabolism by spinal cord neurons after spinal cord injury and identified lipid-lowering compounds to treat spinal cord injury.We found that lipid droplets accumulated in perilesional spinal cord neurons after spinal cord injury in mice.Lipid droplet accumulation could be induced by myelin debris in HT22 cells.Myelin debris degradation by phospholipase led to massive free fatty acid production,which increased lipid droplet synthesis,β-oxidation,and oxidative phosphorylation.Excessive oxidative phosphorylation increased reactive oxygen species generation,which led to increased lipid peroxidation and HT22 cell apoptosis.Bromocriptine was identified as a lipid-lowering compound that inhibited phosphorylation of cytosolic phospholipase A2 by reducing the phosphorylation of extracellular signal-regulated kinases 1/2 in the mitogen-activated protein kinase pathway,thereby inhibiting myelin debris degradation by cytosolic phospholipase A2 and alleviating lipid droplet accumulation in myelin debris-treated HT22 cells.Motor function,lipid droplet accumulation in spinal cord neurons and neuronal survival were all improved in bromocriptine-treated mice after spinal cord injury.The results suggest that bromocriptine can protect neurons from lipotoxic damage after spinal cord injury via the extracellular signal-regulated kinases 1/2-cytosolic phospholipase A2 pathway.

Lupenone improves motor dysfunction in spinal cord injury mice through inhibiting the inflammasome activation and pyroptosis in microglia via the nuclear factor kappa B pathway

Spinal cord injury-induced motor dysfunction is associated with neuroinflammation.Studies have shown that the triterpenoid lupenone,a natural product found in various plants,has a remarkable anti-inflammatory effect in the context of chronic inflammation.However,the effects of lupenone on acute inflammation induced by spinal cord injury remain unknown.In this study,we established an impact-induced mouse model of spinal cord injury,and then treated the injured mice with lupenone(8 mg/kg,twice a day)by intrape ritoneal injection.We also treated BV2 cells with lipopolysaccharide and adenosine5’-triphosphate to simulate the inflammatory response after spinal cord injury.Our res ults showed that lupenone reduced IKBa activation and p65 nuclear translocation,inhibited NLRP3 inflammasome function by modulating nuclear factor kappa B,and enhanced the conve rsion of proinflammatory M1 mic roglial cells into anti-inflammatory M2 microglial cells.Furthermore,lupenone decreased NLRP3 inflammasome activation,NLRP3-induced mic roglial cell polarization,and microglia pyroptosis by inhibiting the nuclear factor kappa B pathway.These findings suggest that lupenone protects against spinal cord injury by inhibiting inflammasomes.

Resident immune responses to spinal cord injury:role of astrocytes and microglia

Spinal cord injury can be traumatic or non-traumatic in origin,with the latter rising in incidence and prevalence with the aging demographics of our society.Moreove r,as the global population ages,individuals with co-existent degenerative spinal pathology comprise a growing number of traumatic spinal cord injury cases,especially involving the cervical spinal cord.This makes recovery and treatment approaches particula rly challenging as age and comorbidities may limit regenerative capacity.For these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiology and the ensuing inflammatory response.This review discusses microglia-specific purinergic and cytokine signaling pathways,as well as microglial modulation of synaptic stability and plasticity after injury.Further,we evaluate the role of astrocytes in neurotransmission and calcium signaling,as well as their border-forming response to neural lesions.Both the inflammatory and reparative roles of these cells have eluded our complete understanding and remain key therapeutic targets due to their extensive structural and functional roles in the nervous system.Recent advances have shed light on the roles of glia in neurotransmission and reparative injury responses that will change how interventions are directed.Understanding key processes and existing knowledge gaps will allow future research to effectively target these cells and harness their regenerative potential.

In vivo imaging of the neuronal response to spinal cord injury:a narrative review

Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are lacking.Emerging in vivo imaging and labeling methods offer great potential for observing dynamic neural processes in the central nervous system in conditions of health and disease.This review first discusses in vivo imaging of the mouse spinal cord with a focus on the latest imaging techniques,and then analyzes the dynamic biological response of spinal cord sensory and motor neurons to SCI.We then summarize and compare the techniques behind these studies and clarify the advantages of in vivo imaging compared with traditional neuroscience examinations.Finally,we identify the challenges and possible solutions for spinal cord neuron imaging.

Infantile Spinal Muscular Atrophy at the Albert Royer National Children’s Hospital Center in Dakar

Introduction: Infantile spinal muscular atrophy (ISA) is an autosomal recessive disease caused by primary degeneration of cells in the anterior horn of the spinal cord, leading to muscle weakness and hypotonia. Its incidence is estimated at 1 in 6000 births worldwide. In Africa, particularly in Senegal, there are few studies interested on this pathology. We therefore deemed this study necessary, which set itself the objective of describing the diagnostic, therapeutic and progressive aspects of infantile spinal muscular atrophy at the Albert Royer National Children’s Hospital Center in Dakar (CHNEAR). Methodology: We conducted a retrospective descriptive study over a period of two (2) years from December 2020 to December 2022. Included were all hospitalized patients in whom the diagnosis of spinal muscular atrophy was made with or without genetic confirmation. The data were collected on a pre-established form then entered and analyzed with the following software: Excel 2013 and R version 4.1.3. Results: During our study period, 2100 children were hospitalized, the annual incidence was 0.76%. The average age of our patients was 9 ± 9 months with a range of 3 months to 32 months and the median was 6.5 months. The sex ratio was 7. The notion of family consanguinity was found in 62.5% of cases and the notion of ISA in the family in 25% of cases. Hypotonia and respiratory distress were found at the forefront in equal proportions (50% of cases). Electromyogram (EMG) was performed in 3 patients (37.5%). Symptomatic medical treatment was administered in 100% of patients, 04 patients had benefited from respiratory physiotherapy, i.e. 50% of cases, and genetic counseling was carried out in one patient (12.5%). The evolution was immediately favorable in 2 patients or 25% of cases, unfavorable in 75% of cases with a death rate of 50% and the average age of death was 5.5 months ± 1 with extremes ranging from 3 to 7 months. Conclusion: The number of Infantile spinal muscular atrophy cases remains low in hospitals in Dakar. Diagnostic means are still difficult to access. The course is difficult to predict and is often marked in the long term by respiratory difficulties which can be fatal.