Current Epidemiology of Intracranial Metastases in Two University Teaching Reference Hospitals of the Town of Yaounde, Cameroon: Analysis of 35 Cases Recorded in the Neurosurgery Departments

Background: The incidence of intracranial metastases (ICMET) has been steadily rising, and its frequency with respect to primary brain tumours is relatively high. Objective: The objectives of this study were to elucidate the current epidemiology and describe the clinical, diagnostic and therapeutic features of ICMET in Yaounde. Method and findings: A descriptive cross-sectional study was done in the neurosurgery departments of the General and Central Hospitals of Yaounde during the period from January 2016 to December 2022. We included all medical booklets of patients admitted for a tumoral intracranial expansive process with our target population being patients with histological evidence of ICMET, and did a retrospective inclusion of data using a pre-established technical form aimed at collecting sociodemographic data, clinical data, paraclinical data, and the treatment procedures. Analysis was done using the SPSS statistical software. A total of 614 cases of intracranial tumors were included among whom 35 presented histological evidence of ICMET. This gives a frequency of 5.7%. The sex ratio was 0.94, the mean age was 55.68 +/- 14.4 years, extremes 28 and 86 years and the age range 50 - 59 was affected in 28.57% of cases. The clinical presentation included signs of raised intracranial pressure (headache, blurred vision, vomiting) in 26 cases (74.3%), motor deficit 48.6%, seizures 17.1%. The mode of onset was metachronous in 71.4% and synchronous in 28.6%. The imaging techniques were cerebral CT scan in 82.9%, cerebral MRI in 40%, TAP scan in 22.9%. The metastatic lesions were supratentorial in 94.3% and single in 62.9%. The primary cancers found were breast cancer (31.4%), lung cancer (25.7%), prostate cancer (17.1%), thyroid cancer (5.7%), colon cancer (2.9%), and melanoma (2.9%). The therapeutic modalities were total resection (68.6%), radiotherapy (37.1%). Conclusion: Intracranial metastases are relatively frequent. There is a female sex predominance and the age group 50 - 59 years is the most affected. Brain metastases mostly occur in patients with a history of known primary tumor. The clinical signs mainly include signs of raised intracranial pressure, motor deficit, seizures and mental confusion. Cerebral CT Scan is the main imaging technique used. Most of the lesions are single and supratentorially located. The primary cancers most represented include breast cancer, lung cancer and prostate cancer. Surgery is the main treatment procedure. The adjuvant treatment (radiotherapy, chemotherapy) was limited.

Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage

The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial dysfunction.Dysfunctional mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging cells.In response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological conditions.Specific interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid hemorrhage.This review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control mechanisms.It also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage.

Sustained release of vascular endothelial growth factor A and basic fibroblast growth factor from nanofiber membranes reduces oxygen/glucose deprivation-induced injury to neurovascular units

Upregulation of vascular endothelial growth factor A/basic fibroblast growth factor(VEGFA/b FGF)expression in the penumbra of cerebral ischemia can increase vascular volume,reduce lesion volume,and enhance neural cell proliferation and differentiation,thereby exerting neuroprotective effects.However,the beneficial effects of endogenous VEGFA/b FGF are limited as their expression is only transiently increased.In this study,we generated multilayered nanofiber membranes loaded with VEGFA/b FGF using layer-by-layer self-assembly and electrospinning techniques.We found that a membrane containing 10 layers had an ideal ultrastructure and could efficiently and stably release growth factors for more than 1 month.This 10-layered nanofiber membrane promoted brain microvascular endothelial cell tube formation and proliferation,inhibited neuronal apoptosis,upregulated the expression of tight junction proteins,and improved the viability of various cellular components of neurovascular units under conditions of oxygen/glucose deprivation.Furthermore,this nanofiber membrane decreased the expression of Janus kinase-2/signal transducer and activator of transcription-3(JAK2/STAT3),Bax/Bcl-2,and cleaved caspase-3.Therefore,this nanofiber membrane exhibits a neuroprotective effect on oxygen/glucose-deprived neurovascular units by inhibiting the JAK2/STAT3 pathway.

The miR-9-5p/CXCL11 pathway is a key target of hydrogen sulfide-mediated inhibition of neuroinflammation in hypoxic ischemic brain injury

We previously showed that hydrogen sulfide(H2S)has a neuroprotective effect in the context of hypoxic ischemic brain injury in neonatal mice.However,the precise mechanism underlying the role of H2S in this situation remains unclear.In this study,we used a neonatal mouse model of hypoxic ischemic brain injury and a lipopolysaccharide-stimulated BV2 cell model and found that treatment with L-cysteine,a H2S precursor,attenuated the cerebral infarction and cerebral atrophy induced by hypoxia and ischemia and increased the expression of miR-9-5p and cystathionineβsynthase(a major H2S synthetase in the brain)in the prefrontal cortex.We also found that an miR-9-5p inhibitor blocked the expression of cystathionineβsynthase in the prefrontal cortex in mice with brain injury caused by hypoxia and ischemia.Furthermore,miR-9-5p overexpression increased cystathionine-β-synthase and H2S expression in the injured prefrontal cortex of mice with hypoxic ischemic brain injury.L-cysteine decreased the expression of CXCL11,an miR-9-5p target gene,in the prefrontal cortex of the mouse model and in lipopolysaccharide-stimulated BV-2 cells and increased the levels of proinflammatory cytokines BNIP3,FSTL1,SOCS2 and SOCS5,while treatment with an miR-9-5p inhibitor reversed these changes.These findings suggest that H2S can reduce neuroinflammation in a neonatal mouse model of hypoxic ischemic brain injury through regulating the miR-9-5p/CXCL11 axis and restoringβ-synthase expression,thereby playing a role in reducing neuroinflammation in hypoxic ischemic brain injury.

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.

Melatonin improves synapse development by PI3K/Akt signaling in a mouse model of autism spectrum disorder

Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes,including Ctnnd2 as a candidate gene.Ctnnd2knockout mice,serving as an animal model of autis m,have been demonstrated to exhibit decreased density of dendritic spines.The role of melatonin,as a neuro hormone capable of effectively alleviating social interaction deficits and regulating the development of dendritic spines,in Ctnnd2 deletion-induced nerve injury remains unclea r.In the present study,we discove red that the deletion of exon 2 of the Ctnnd2 gene was linked to social interaction deficits,spine loss,impaired inhibitory neurons,and suppressed phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt) signal pathway in the prefrontal cortex.Our findings demonstrated that the long-term oral administration of melatonin for 28 days effectively alleviated the aforementioned abnormalities in Ctnnd2 gene-knockout mice.Furthermore,the administration of melatonin in the prefro ntal cortex was found to improve synaptic function and activate the PI3K/Akt signal pathway in this region.The pharmacological blockade of the PI3K/Akt signal pathway with a PI3K/Akt inhibitor,wo rtmannin,and melatonin receptor antagonists,luzindole and 4-phenyl-2-propionamidotetralin,prevented the melatonin-induced enhancement of GABAergic synaptic function.These findings suggest that melatonin treatment can ameliorate GABAe rgic synaptic function by activating the PI3K/Akt signal pathway,which may contribute to the improvement of dendritic spine abnormalities in autism spectrum disorders.

Effects of exosomes from mesenchymal stem cells on functional recovery of a patient with total radial nerve injury: A pilot study

BACKGROUND Peripheral nerve injury can result in significant clinical complications that have uncertain prognoses.Currently,there is a lack of effective pharmacological interventions for nerve damage,despite the existence of several small compounds,Despite the objective of achieving full functional restoration by surgical intervention,the persistent challenge of inadequate functional recovery remains a significant concern in the context of peripheral nerve injuries.AIM To examine the impact of exosomes on the process of functional recovery following a complete radial nerve damage.METHODS A male individual,aged 24,who is right-hand dominant and an immigrant,arrived with an injury caused by a knife assault.The cut is located on the left arm,specifically below the elbow.The neurological examination and electrodiagnostic testing reveal evidence of left radial nerve damage.The sural autograft was utilized for repair,followed by the application of 1 mL of mesenchymal stem cell-derived exosome,comprising 5 billion microvesicles.This exosome was split into four equal volumes of 0.25 mL each and delivered microsurgically to both the proximal and distal stumps using the subepineural pathway.The patient was subjected to a period of 180 d during which they had neurological examination and electrodiagnostic testing.RESULTS The duration of the patient’s follow-up period was 180 d.An increasing Tinel’s sign and sensory-motor recovery were detected even at the 10th wk following nerve grafting.Upon the conclusion of the 6-mo post-treatment period,an evaluation was conducted to measure the extent of improvement in motor and sensory functions of the nerve.This assessment was based on the British Medical Research Council scale and the Mackinnon-Dellon scale.The results indicated that the level of improvement in motor function was classified as M5,denoting an excellent outcome.Additionally,the level of improvement in sensory function was classified as S3+,indicating a good outcome.It is noteworthy that these assessments were conducted in the absence of physical therapy.At the 10th wk post-injury,despite the persistence of substantial axonal damage,the nerve exhibited indications of nerve re-innervation as evidenced by control electromyography(EMG).In contrast to the preceding.EMG analysis revealed a significant electrophysiological enhancement in the EMG conducted at the 6th-mo follow-up,indicating ongoing regeneration.CONCLUSION Enhanced comprehension of the neurobiological ramifications associated with peripheral nerve damage,as well as the experimental and therapy approaches delineated in this investigation,holds the potential to catalyze future clinical progress.

Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex

Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction.

Treadmill exercise improves hippocampal neural plasticity and relieves cognitive deficits in a mouse model of epilepsy

Epilepsy frequently leads to cognitive dysfunction and approaches to treatment remain limited.Although regular exercise effectively improves learning and memory functions across multiple neurological diseases,its application in patients with epilepsy remains controversial.Here,we adopted a 14-day treadmill-exercise paradigm in a pilocarpine injection-induced mouse model of epilepsy.Cognitive assays confirmed the improvement of object and spatial memory after endurance training,and electrophysiological studies revealed the maintenance of hippocampal plasticity as a result of physical exercise.Investigations of the mechanisms underlying this effect revealed that exercise protected parvalbumin interneurons,probably via the suppression of neuroinflammation and improved integrity of blood-brain barrier.In summary,this work identified a previously unknown mechanism through which exercise improves cognitive rehabilitation in epilepsy.

Preliminary Recommendations for Surgical Practice of Neurosurgery Department in the Central Epidemic Area of 2019 Coronavirus Infection

Since December 2019,an outbreak of coronavirus disease 2019(COVID-19)has.posed significant threats to the public health and life in China.Unlike the other 6 identified coronaviruscs,the SARS-Cov-2 has a high infectious rate,a long incubation period and a variety of manifestations.In the absence of effective treatments for the virus,it becomes extremely urgent to develop scientific and standardized proposals for prevention and control of virus transmission.Hereby we focused on the surgical practice in Neurosurgery Department,Tongji Hospital,Wuhan,and drafted several recommendations based on the latest relevant guidelines and our experience.These recommendations have helped us until now to achieve'zero infection'of doctors and nurses in our department,we would like to share them with other medical staff of neurosurgery to fight 2019-nCoV infection.

Exploring cerebral structural and functional abnormalities in a mouse model of post-traumatic headache induced by mild traumatic brain injury

Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability worldwide.Although PTH is often accompanied by neurological disorders,the exact underlying mechanism remains largely unknown.Identifying potential biomarkers may prompt the diagnosis and development of effective treatments for mTBI-induced PTH.In this study,a mouse model of mTBI-induced PTH was established to investigate its effects on cerebral structure and function during short-term recovery.Results indicated that mice with mTBI-induced PTH exhibited balance deficits during the early post-injury stage.Metabolic kinetics revealed that variations in neurotransmitters were most prominent in the cerebellum,temporal lobe/cortex,and hippocampal regions during the early stages of PTH.Additionally,variations in brain functional activities and connectivity were further detected in the early stage of PTH,particularly in the cerebellum and temporal cortex,suggesting that these regions play central roles in the mechanism underlying PTH.Moreover,our results suggested that GABA and glutamate may serve as potential diagnostic or prognostic biomarkers for PTH.Future studies should explore the specific neural circuits involved in the regulation of PTH by the cerebellum and temporal cortex,with these two regions potentially utilized as targets for non-invasive stimulation in future clinical treatment.

Are EPB41 and alpha-synuclein diagnostic biomarkers of sport-related concussion?Findings from the NCAA and Department of Defense CARE Consortium

Background:Current protein biomarkers are only moderately predictive at identifying individuals with mild traumatic brain injury or concussion.Therefore,more accurate diagnostic markers are needed for sport-related concussion.Methods:This was a multicenter,prospective,case-control study of athletes who provided blood samples and were diagnosed with a concussion or were a matched non-concussed control within the National Collegiate Athletic Association-Department of Defense Concussion Assessment,Research,and Education Consortium conducted between 2015 and 2019.The blood was collected within 48 h of injury to identify protein abnormalities at the acute and subacute timepoints.Athletes with concussion were divided into 6 h post-injury(0-6 h post-injury)and after 6 h postinjury(7-48 h post-injury)groups.We applied a highly multiplexed proteomic technique that used a DNA aptamers assay to target 1305proteins in plasma samples from athletes with and without sport-related concussion.Results:A total of 140 athletes with concussion(79.3%males;aged 18.71±1.10 years,mean±SD)and 21 non-concussed athletes(76.2%males;19.14±1.10 years)were included in this study.We identified 338 plasma proteins that significantly differed in abundance(319 upregulated and 19 downregulated)in concussed athletes compared to non-concussed athletes.The top 20 most differentially abundant proteins discriminated concussed athletes from non-concussed athletes with an area under the curve(AUC)of 0.954(95%confidence interval:0.922-0.986).Specifically,after 6 h of injury,the individual AUC of plasma erythrocyte membrane protein band 4.1(EPB41)and alpha-synuclein(SNCA)were 0.956 and 0.875,respectively.The combination of EPB41 and SNCA provided the best AUC(1.000),which suggests this combination of candidate plasma biomarkers is the best for diagnosing concussion in athletes after 6 h of injury.Conclusion:Our data suggest that proteomic profiling may provide novel diagnostic protein markers and that a combination of EPB41 and SNCA is the most predictive biomarker of concussion after 6 h of injury.

Transcriptomic and bioinformatics analysis of the mechanism by which erythropoietin promotes recovery from traumatic brain injury in mice

Recent studies have found that erythropoietin promotes the recovery of neurological function after traumatic brain injury.However,the precise mechanism of action remains unclea r.In this study,we induced moderate traumatic brain injury in mice by intrape ritoneal injection of erythro poietin for 3 consecutive days.RNA sequencing detected a total of 4065 differentially expressed RNAs,including 1059 mRNAs,92 microRNAs,799 long non-coding RNAs,and 2115circular RNAs.Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses revealed that the coding and non-coding RNAs that were differentially expressed after traumatic brain injury and treatment with erythropoietin play roles in the axon guidance pathway,Wnt pathway,and MAPK pathway.Constructing competing endogenous RNA networks showed that regulatory relationship between the differentially expressed non-coding RNAs and mRNAs.Because the axon guidance pathway was repeatedly enriched,the expression of Wnt5a and Ephb6,key factors in the axonal guidance pathway,was assessed.Ephb6 expression decreased and Wnt5a expression increased after traumatic brain injury,and these effects were reversed by treatment with erythro poietin.These findings suggest that erythro poietin can promote recove ry of nerve function after traumatic brain injury through the axon guidance pathway.

Growth hormone promotes the reconstruction of injured axons in the hypothalamo-neurohypophyseal system

Previous studies have shown that growth hormone can regulate hypothalamic energy metabolism, stress, and hormone release. Therefore, growth hormone has great potential for treating hypothalamic injury. In this study, we established a specific hypothalamic axon injury model by inducing hypothalamic pituitary stalk electric lesions in male mice. We then treated mice by intraperitoneal administration of growth hormone. Our results showed that growth hormone increased the expression of insulin-like growth factor 1 and its receptors, and promoted the survival of hypothalamic neurons, axonal regeneration, and vascular reconstruction from the median eminence through the posterior pituitary. Altogether, this alleviated hypothalamic injury-caused central diabetes insipidus and anxiety. These results suggest that growth hormone can promote axonal reconstruction after hypothalamic injury by regulating the growth hormone-insulin-like growth factor 1 axis.

Therapeutic potential of stem cells in subarachnoid hemorrhage

Aneurysm rupture can result in subarachnoid hemorrhage,a condition with potentially severe consequences,such as disability and death.In the acute stage,early brain injury manifests as intracranial pressure elevation,global cerebral ischemia,acute hydrocephalus,and direct blood–brain contact due to aneurysm rupture.This may subsequently cause delayed cerebral infarction,often with cerebral vasospasm,significantly affecting patient outcomes.Chronic complications such as brain volume loss and chronic hydrocephalus can further impact outcomes.Investigating the mechanisms of subarachnoid hemorrhage-induced brain injury is paramount for identifying effective treatments.Stem cell therapy,with its multipotent differentiation capacity and anti-inflammatory effects,has emerged as a promising approach for treating previously deemed incurable conditions.This review focuses on the potential application of stem cells in subarachnoid hemorrhage pathology and explores their role in neurogenesis and as a therapeutic intervention in preclinical and clinical subarachnoid hemorrhage studies.

Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via miR-146a-5p-mediated regulation of macrophage polarization

Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury.

Gabapentinoids for the treatment of stroke

Gabapentinoid drugs(pregabalin and gabapentin) have been successfully used in the treatment of neuro pathic pain and in focal seizure prevention.Recent research has demonstrated their potent activities in modulating neurotransmitter release in neuronal tissue,oxidative stress,and inflammation,which matches the mechanism of action via voltage-gated calcium channels.In this review,we briefly elaborate on the medicinal history and ligand-binding sites of gabapentinoids.We systematically summarize the preclinical and clinical research on gabapentinoids in stroke,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,seizures after stro ke,cortical spreading depolarization after stroke,pain after stroke,and nerve regeneration after stro ke.This review also discusses the potential to rgets of gabapentinoids in stroke;however,the existing results are still unce rtain regarding the effect of gabapentinoids on stroke and related diseases.Further preclinical and clinical trials are needed to test the therapeutic potential of gabapentinoids in stroke.Therefore,gabapentinoids have both opportunities and challenges in the treatment of stroke.

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

Metformin alleviates spinal cord injury by inhibiting nerve cell ferroptosis through upregulation of heme oxygenase-1 expression

Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox homeostasis.Metformin is a classic drug used to treat type 2 diabetes that can inhibit ferroptosis.Previous studies have shown that,when used to treat cardiovascular and digestive system diseases,metformin can also upregulate heme oxygenase-1 expression.Therefore,we hypothesized that heme oxygenase-1 plays a significant role in mediating the beneficial effects of metformin on neuronal ferroptosis after spinal cord injury.To test this,we first performed a bioinformatics analysis based on the GEO database and found that heme oxygenase-1 was upregulated in the lesion of rats with spinal cord injury.Next,we confirmed this finding in a rat model of T9 spinal cord compression injury that exhibited spinal cord nerve cell ferroptosis.Continuous intraperitoneal injection of metformin for 14 days was found to both upregulate heme oxygenase-1 expression and reduce neuronal ferroptosis in rats with spinal cord injury.Subsequently,we used a lentivirus vector to knock down heme oxygenase-1 expression in the spinal cord,and found that this significantly reduced the effect of metformin on ferroptosis after spinal cord injury.Taken together,these findings suggest that metformin inhibits neuronal ferroptosis after spinal cord injury,and that this effect is partially dependent on upregulation of heme oxygenase-1.