Spinal Cord Injury Group Research Articles

ScRNA-Seq reveals age-dependent microglial evolution as a determinant of immune response following spinal cord injury

Spinal cord injury (SCI) is a debilitating condition of the central nervous system (CNS) that leads to severe impairments in sensory and motor functions. Previous studies have pointed out that patient age is a critical factor influencing SCI prognosis. However, the role of microglia in age-related differences in SCI outcomes remains unclear. The current study aims to identify specific microglial subtypes and investigate their responses and functional differences in SCI recovery across different age groups. Single-cell RNA sequencing (scRNA-seq) data were obtained from the Gene Expression Omnibus (GEO) database, integrating multiple datasets to identify microglial subtypes. We performed pseudotime trajectory analysis and cell-cell communication analysis to understand microglial differentiation and interactions. Finally, immunofluorescence staining of mouse model samples was conducted to validate our bioinformatics findings. Microglia were classified into four subtypes: Homeostatic, Proliferating, Inflammatory A, and Inflammatory B. The Young SCI group exhibited a higher proportion of Homeostatic microglia and Inflammatory microglia A, whereas the old SCI group had more Inflammatory Microglia B but lacked Homeostatic Microglia. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that markers for homeostasis microglia were enriched in immune modulation pathways. While makers for Inflammatory Microglia were enriched in immune response pathways. Specifically, markers for Inflammatory microglia B were enriched in pathways associated with overactive immune response. Pseudotime analysis indicated that microglia in young mice predominantly differentiated into Inflammatory Microglia A and Homeostatic Microglia, whereas in old mice, they tended to only differentiate into Inflammatory Microglia B. CellChat analysis showed increased pro-inflammatory signaling generated by Inflammatory Microglia B, exclusively in the old group. Our study demonstrates significant differences in microglial subtypes and functions between different age groups following SCI. These findings provide novel insights into the development of age-related therapeutic strategies and microglia-targeted biological treatments for SCI.

Human Amniotic Epithelial Stem Cells Promote Functional Recovery After Spinal Cord Injury In Rats By Regulating The Polarization Of Macrophages.

Spinal cord injury (SCI) is a catastrophic nerve injury caused by extremelysevere damage to thespinalcord, for which effective treatments are currently unavailable. Human amniotic epithelial stem cells (hAESCs) are considered promising candidates for transplantation in various clinical and preclinical applications, due to their lack of limitations such as ethical barriers, immune rejection, tumorigenicity, or cell origin. Nevertheless, the effectiveness and mechanism by which hAESCs treat SCI remain elusive.To assess the motor function recovery process following SCI in rats, the Basso Beattie Bresnahan (BBB) behavior test, inclined plate scale and motor evoked potential (MEP) analysis were used in this study after transplantation of hAESCs at different doses. And the underlying mechanism was investigated by histological and molecular methods. The transplantation of hAESCs can significantly promote the recovery of motor function in SCI group, and the higher the dose, the better the effect. Compared with SCI group, hAESCs group had reduced tissue damage, significantly increased the number of neurons, neurofilaments and myelin sheath, and significantly reduced syringomyelia and glial scars. In addition, hAESCs inhibited the Levels of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) and increased the expression of the interleukin-4 (IL-4), interleukin-10 (IL-10) and interleukin-13 (IL-13), and promoted the shift of M1-polarized macrophages to M2-polarized macrophages. Our results demonstrate that hAESCs promoted the recovery of motor function after SCI by promoting M2 polarization of macrophages and reducing neuroinflammation.These findings may provide novel therapeutic strategies for SCI.

Effect of Electrical Stimulation of the Vagus Nerve on Inflammation in Rats With Spinal Cord Injury

ObjectiveThe purpose of this study was to assess the effect of electroacupuncture stimulation (EAS) of the vagus nerve on the inflammatory response in rat models of spinal cord injury (SCI). MethodsThe T10 SCI model in adult male Sprague Dawley rats was established using the modified Allen's method. The EAS group was treated with the therapy on the vagus nerve of rat ear nails, while the SCI group did not receive any EAS treatment. The degree of inflammatory infiltration was reflected by hematoxylin-eosin staining. The inflammatory cytokines in spinal cord tissues, cerebrospinal fluid inflammation, and peripheral blood were detected by enzyme-linked immunosorbent assay. Changes in astrocytes and microglia were assessed using an immunofluorescence assay. ResultsElectroacupuncture stimulation treatment inhibited inflammatory infiltration, as well as the concentrations of interleukin-6, interleukin-1β, tumor necrosis factor-α, astrocytes, and microglia at 1, 6, and 24 hours after 1 EAS treatment. Multiple EAS treatments had an obvious effect on SCI inflammation. ConclusionA single EAS treatment had a limited effect on inflammation, but multiple treatments had a significant inhibitory effect on inflammation.

Cold atmospheric plasma-activated saline alleviates secondary injury post-SCI by inhibiting extracellular matrix remodeling and infiltration of proinflammatory macrophages

BackgroundCold atmospheric plasma (CAP) has been shown to improve the recovery of transected peripheral nerves. We determined the protective role of CAP-activated saline (CAP-AS) treatment in the acute and subacute stages of spinal cord injury (SCI) in mice. MethodsC57BL/6 SCI mice were treated with CAP-AS for 14 days. Injury recovery was assessed weekly for four weeks by conducting motor function tests, including the Basso Mouse Scale (BMS) and footprint test. Transcriptome analysis was conducted on day 14 to elucidate potential mechanisms, which were further validated through immunofluorescence examinations of the injured spinal cord tissues on day 28 and the levels of proinflammatory cytokines produced by macrophages in vitro. ResultsCompared to the SCI group, the CAP-AS-treated groups presented significantly better hindlimb motor function after four weeks. The downregulated (SCI vs. SCI + CAP-AS, with CAP-AS activated for 20 min) differentially expressed genes (DEGs) were enriched in the extracellular region, extracellular matrix (ECM), and ECM-receptor interaction. In contrast, the upregulated DEGs were enriched in immune response-associated pathways. Histological changes in the CAP-AS-treated groups were observed to further validate the predicted mechanisms 28 days post-injury. The alleviation of secondary injury was confirmed by an increase in GFAP-positive and NFH-positive areas, and enhanced outgrowth of 5-HT-positive fibers. Inhibited ECM remodeling was confirmed by a decrease in the areas positive for PDGFRβ, fibronectin, and laminin. A decrease in the infiltration of macrophages and activation of microglia was determined by a decrease in CD68-positive and F4/80-positive areas. The inhibitory effect of CAP-AS on inflammation was further supported by a decrease in the levels of the proinflammatory cytokines IL-1β, IL-6, and TNF-α in CAP-AS-treated M1 macrophages. ConclusionCAP-AS can alleviate secondary injury in SCI model mice by inhibiting ECM remodeling in injured tissues and reducing the infiltration or activation of proinflammatory macrophages/microglia.

Herbal Treatment for Paralysis

Paralysis is when a person can not move or feel a part of their body. It happens when something goes wrong with the brain cells or nerves that control movement. It can be caused by inflammation, injuries, strokes, or diseases. A condition known as sleep paralysis (SP) refers to the immobility that sets in while a person is either sleeping or barely awake. It could manifest as isolated SP in healthy persons. Additionally, it has been linked to sleep, family, and other underlying psychiatric illnesses. According to the ratio, 8% of people in general have SP. Despite erroneous descriptions of this value, there is no accepted definition for the diagnosis of sleep paralysis. The literature now in publication describes SP for a number of reasons. One might see that these descriptions are either medically or culturally based. The disparity in SP diagnosis between medical professionals and members of cultural or ethnic groups has resulted in a variety of management strategies. The purpose of this review is to list medical. The exact method of action of stem cells is unknown. Objective: The aim of this study is to ascertain and contrast the prevalence, characteristics, neurological manifestation, and functional result of individuals suffering from nontraumatic spinal cord injury (SCI) with those suffering from traumatic SCI. 39% of SCI hospitalizations had a nontraumatic cause (tumor, 26%; spinal stenosis, 54%). Subjects with nontraumatic SCI were substantially (p <.01) older, more likely to be married, female, and retired than those with traumatic SCI. Within the nontraumatic SCI group, injury characteristics showed significantly higher rates of paraplegia and incomplete SCI (p <.01). From the time of admission to rehabilitation until the time of discharge, both nontraumatic and traumatic SCI patients experienced significant FIM changes (p <.01). Comparing the traumatic group to the nontraumatic SCI group, those with tetraplegia-incomplete group had significantly higher admission motor FIM scores and shorter rehabilitation duration of stay (p <.05). Compared to those with traumatic SCI, paraplegic-complete and paraplegic-incomplete nontraumatic SCI participants showed lower discharge motor FIM scores, FIM change, and FIM efficiency. Comparable rates of discharge to the home were observed in nontraumatic. This study aimed to examine the spinal cord injury experiences of younger and older individuals. Age at injury data from 866 hospitalized patients between 1973 and 1985 were examined. Results were assessed both two years following the injury and at discharge. Compared to patients aged 16 to 30, patients aged 61 or older had 2.1 times higher odds of developing pneumonia, 2.7 times higher odds of experiencing a gastrointestinal hemorrhage, 5.6 times higher odds of developing pulmonary emboli, and 16.8 times higher odds of having renal stones prior to first definitive discharge. In the second year following their accident, patients who were at least 61 years old had a 3.9-fold increased risk of being readmitted to the hospital.

MRI-based assessment paraspinal extensor muscle fatty infiltration in acute cervical spinal cord injury patients - a retrospective study

BackgroundThe effect of fat infiltration in the paraspinal muscles on cervical degenerative disease has been confirmed by multiple studies. However, little is known about fat infiltration in the paraspinal extensors in patients with acute cervical spinal cord injury (SCI). This study aimed to investigate the difference in paraspinal extensor fatty infiltration between patients with acute cervical SCI and healthy controls, and to further explore the protective role of the paravertebral extensor muscles in patients with cervical SCI.MethodsA total of 50 patients with acute cervical SCI admitted to the emergency department from January 2019 to November 2023 were retrospectively analyzed, including 26 males and 24 females, with an average age of 59.60 ± 10.81 years. A control group of 50 healthy middle-aged and elderly individuals was also included, comprising 28 males and 22 females, with an average age of 55.00 ± 8.21 years. Cervical spine magnetic resonance imaging (MRI) was used to measure the cross-sectional areas of the superficial and deep cervical extensor muscles, the corresponding vertebral body cross-sectional areas, and the fat area within the superficial and deep extensor muscle groups using Image J software. Differences between the two groups were compared, and the cervical SCI patients were further analyzed based on the severity of the spinal cord injury and gender differences.ResultsThe deep fatty infiltration ratio (DFIR) and superficial fatty infiltration ratio (SFIR) at C4-C7 in the cervical SCI group were significantly higher than those in the control group (P < 0.001). The cross-sectional area of the functional deep extensor area (FDEA) relative to the vertebral body area (VBA) and the cross-sectional area of the functional superficial extensor area (FSEA) relative to the VBA at the C5 and C6 levels in the cervical SCI group were significantly lower than those in the control group (P < 0.001, P < 0.001, P = 0.034, P = 0.004 respectively). Among the cervical SCI patients, the cross-sectional areas of the deep extensor area (DEA) and the superficial extensor area (SEA) in males were significantly higher than those in females (P < 0.001). At the C6 and C7 levels, the FDEA/VBA and FSEA/VBA ratios in the male group were higher than those in the female group (P = 0.009, P = 0.022, P = 0.019, P = 0.005, respectively).ConclusionPatients with acute cervical SCI exhibit significantly higher fatty infiltration and a greater degree of paravertebral extensor muscle degeneration compared to healthy controls. This finding underscores the importance of the paravertebral extensor muscles in the context of cervical SCI and may guide future therapeutic strategies.

Buyang Huanwu decoction promotes angiogenesis and improves hemorheological parameters after cervical spinal cord injury

ObjectiveTo explore the effects of Buyang Huanwu decoction (BYHWD) on vascular neogenesis and hemorheological parameters following cervical spinal cord injury (SCI). MethodsAn acute cervical SCI model was established using 84 female Sprague–Dawley rats. Functional recovery of the rats was evaluated using the forelimb locomotor scale score, forelimb grip strength test, and Basso-Beattie-Bresnahan score. The animals were subsequently euthanized at days 7 and 28 postoperatively. The gross morphology, neuronal survival, and myelin sheath in the injured area were evaluated using hematoxylin and eosin (HE), Nissl, and luxol fast blue (LFB) staining, respectively. Immunofluorescence staining was used to observe CD31 expression 7 days post-injury. Furthermore, the expression of CD31, neuronal nuclear protein (NeuN), and myelin basic protein (MBP) were evaluated 28 days post-injury. Additionally, vascular endothelial growth factor A (VEGFA) and VEGF receptor-2 (VEGFR-2) expression was evaluated using western blotting. Whole-blood viscosity, plasma viscosity, and red blood cell aggregation were measured using a hemorheometer. ResultsFrom postoperative days 3–28, motor function in the BYHWD group began to recover considerably compared to the SCI group. BYHWD effectively restored spinal cord histopathology. In addition, the number of NeuN-positive cells, and fluorescence intensity of CD31at 7 and 28 days and MBP significantly increased in the BYHWD group compared with the SCI group (all P < 0.05). Moreover, this decoction significantly upregulated the expression of VEGFA and VEGFR-2 (all P < 0.05). BYHWD improved the hemorheology results (i.e., except erythrocyte aggregation index in the low-dose group), revealing statistically significant differences compared with the SCI group (all P < 0.05). ConclusionBYHWD effectively promoted angiogenesis, improved hemorheological parameters, and protected neurons and myelin sheaths, ultimately promoting the recovery of neurological function after cervical SCI in rats. These findings suggest that BYHWD promotes vascular neogenesis through the VEGFA/VEGFR-2 pathway.

Single-cell RNA sequencing integrated with bulk RNA sequencing analysis reveals the protective effects of lactate-mediated lactylation of microglia-related proteins on spinal cord injury.

Spinal cord injury (SCI) results in significant neurological deficits, and microglia play the critical role in regulating the immune microenvironment and neurological recovery. Protein lactylation has been found to modulate the function of immune cells. Therefore, this study aimed to elucidate the effects of glycolysis-derived lactate on microglial function and its potential neuroprotective mechanisms via lactylation after SCI. Single-cell RNA sequencing (scRNA-seq) data were obtained from figshare to analyze cellular and molecular alterations within the spinal cord post-SCI, further focusing on the expression of microglia-related genes for cell sub-clustering, trajectory analysis, and glycolysis function analysis. We also evaluated the expression of lactylation-related genes in microglia between day 7 after SCI and sham group. Additionally, we established the mice SCI model and performed the bulk RNA sequencing in a time-dependent manner. The expression of glycolysis- and lactylation-related genes was evaluated, as well as the immune infiltration analysis based on the lactylation-related genes. Then, we investigated the bio-effects of lactate on the inflammation and polarization phenotype of microglia. Finally, adult male C57BL/6 mice were subjected to exercise first to increase lactate level, before SCI surgery, aiming to evaluate the protective effects of lactate-mediated lactylation of microglia-related proteins on SCI. scRNA-seq identified a subcluster of microglia, recombinant chemokine C-X3-C-motif receptor 1+ (CX3CR1+) microglia, which is featured by M1-like phenotype and increased after SCI. KEGG analysis revealed the dysfunctional glycolysis in microglia after SCI surgery, and AUCell analysis suggested that the decreased glycolysis an increased oxidative phosphorylation in CX3CR1+ microglia. Differential gene analysis suggested that several lactylation-related genes (Fabp5, Lgals1, Vim, and Nefl) were downregulated in CX3CR1+ microglia at day 7 after SCI, further validated by the results from bulk RNA sequencing. Immunofluorescence staining indicated the expression of lactate dehydrogenase A (LDHA) in CX3CR1+ microglia also decreased at day 7 after SCI. Cellular experiments demonstrated that the administration of lactate could increase the lactylation level and inhibit the pro-inflammatory phenotype in microglia. Functionally, exercise-mediated lactate production resulted in improved locomotor recovery and decreased inflammatory markers in SCI mice compared to SCI alone. In the subacute phase of SCI, metabolic remodeling in microglia may be key therapeutic targets to promote nerve regeneration, and lactate contributed to neuroprotection after SCI by influencing microglial lactylation and inflammatory phenotype, which offered a novel approach for therapeutic intervention.

Association of Microbleeds on Susceptibility-Weighted Imaging with Ferroptosis and Prognosis in Rabbits with Spinal Cord Injury.

Susceptibility-weighted imaging (SWI) is a common imaging technique used to identify cerebral microbleeds. Given that spinal cord injury (SCI) often creates an environment that favors ferroptosis, a type of cell death driven by iron, this study aimed to explore the relationship between microbleeds on SWI and ferroptosis, and explore the effect of deferoxamine on SCI. Thirty-six rabbits were divided into three groups: sham, SCI, and SCI with deferoxamine (DFO, a ferroptosis inhibitor) treatment (SCI+DFO). Following 48 hours of SCI modeling, the rabbits underwent magnetic resonance imaging (MRI) and SWI examinations. Ferroptosis markers and spinal cord tissue morphology were examined, and the modified Tarlov's score was used to assess neurological function. SWI analysis revealed that rabbits in the SCI group exhibited lower signal intensities and larger microbleed areas compared to the those in the SCI+DFO group (p < 0.05). The SCI+DFO group demonstrated significantly decreased iron and malondialdehyde (MDA) levels, coupled with increased glutathione (GSH) and glutathione peroxidase 4 (GPX4) levels, along with attenuated ferroptosis (p < 0.05). This group also displayed greater Neuronal Nuclei (NeuN) expression, Tarlov's scores, and neurological recovery rates (all p < 0.05). A significant positive correlation was found between the microbleed area and iron content (r = 0.59, p = 0.04), MDA (r = 0.75, p = 0.01), and mitochondrial damage (r = 0.90, p < 0.01). Conversely, a negative correlation was established between the microbleed area and GPX4 levels (r = -0.87, p < 0.01), as well as neurological function recovery (r = -0.62, p = 0.03). The extent of microbleeds on SWI following SCI is closely correlated with ferroptosis, and the inhibition of ferroptosis could improve neurologic function. These findings suggest that the area of microbleeds on SWI could potentially serve as a predictive marker for ferroptosis in spinal cord injury.

Effect of Sakuranetin on Microglia-Mediated Neuroinflammation After Spinal Cord Injury

Objective To investigate the effects of sakuranetin (SK) on motor functions in the mouse model of spinal cord injury (SCI) and decipher the mechanism.Methods Fifty-four C57BL/6J mice were randomized into sham,SCI,and SK groups.The mice in the sham group underwent only laminectomy at T9,while those in the SCI and SK groups were subjected to spinal cord contusion injury at T9.Behavioral tests were conducted at different time points after surgery to evaluate the motor functions of mice in each group.The pathological changes in the tissue were observed to assess the extent of SCI in each group.The role and mechanism of SK in SCI were predicted by gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses.Reverse transcription real-time fluorescence quantitative PCR,ELISA,and immunofluorescence were employed to evaluate the inflammation and activation of microglia in SCI mice.BV2 cells in vitro were classified into control (Con),lipopolysaccharide (LPS),and LPS+SK groups.The effects of SK intervention on the release of inflammatory cytokines and the activation of BV2 cells were evaluated.Furthermore,the phosphatidylinositol-3-kinase(PI3K)/protein kinase B (AKT) signaling pathway activator insulin-like growth factor-1 (IGF-1) was used to treat the SK-induced BV2 cells in vitro (SK+IGF-1 group),and SK was used to treat the IGF-1-induced BV2 cells in vitro (IGF-1+SK group).Western blotting was conducted for molecular mechanism validation.Results Behavioral tests and histological staining results showed that compared with the SCI group,the SK group exhibited improved motor abilities and reduced area of damage in the spinal cord tissue (all P<0.001).The GO enrichment analysis predicted that SK may be involved in the inflammation following SCI.The KEGG enrichment analysis predicted that SK regulated the PI3K/Akt pathway to exert the neuroprotective effect.The results from in vitro and in vivo experiments showed that SK lowered the levels of tumor necrosis factor-α,interleukin-6,and interleukin-1β and inhibited the activation of microglia (all P<0.05).The results of Western blotting showed that SK down-regulated the phosphorylation levels of PI3K and Akt (all P<0.001) and inhibited the IGF-1-induced elevation of PI3K and Akt phosphorylation levels (all P<0.001).Conversely,IGF-1 had the opposite effects (P=0.001,P<0.001).The results of reverse transcription real-time fluorescence quantitative PCR,ELISA,and immunofluorescence showed that the SK+IGF-1 group had higher levels of inflammatory cytokines and more activated microglia than the SK group(all P<0.05).Conclusion SK may suppress the activation of the PI3K/Akt pathway to inhibit the inflammation mediated by SCI-induced activation of microglia,ameliorate the pathological damage of the spinal cord tissue,and promote the recovery of motor functions in SCI mice.

Serotonin (5-HT)2A/2C receptor agonist 2,5-dimethoxy-4-iodophenyl-2-aminopropane hydrochloride improves detrusor sphincter dyssynergia by inhibiting L-type voltage-gated calcium channels in spinal cord injured rats.

To explore the role of voltage-gated calcium channels (VGCC) in 5-HT2A/2C receptor agonist 2,5-dimethoxy-4-iodophenyl-2-aminopropane hydrochloride's improvement of spinal cord injury (SCI) induced detrusor sphincter dyssynergia and the expressions of the 5-hydroxy tryptamine (5-HT) 2A receptors and VGCCs in lumbosacral cord after SCI. Female Sprague-Dawley rats were randomized into normal control group and SCI group (N = 15 each). Cystometrogram (CMG), simultaneous CMG, and external urethral sphincter electromyography (EUS-EMG) were conducted in all groups under urethane anesthesia. Drugs were administered intrathecally during CMG and EUS-EMG. Rats were euthanized and L6-S1 spinal cord were acquired for immunofluorescence. In SCI rats, intrathecal administration of 2,5-dimethoxy-4-iodophenyl-2-aminopropane hydrochloride or L-type VGCC blocker, nifedipine, could significantly increase voiding volume, voiding efficiency, and the number of high-frequency oscillations. They could also prolong EUS bursting activity duration on EUS-EMG. Moreover, the effect of 2,5-dimethoxy-4-iodophenyl-2-aminopropane hydrochloride can be eliminated with the combined administration of L-type VGCC agonist, (±)-Bay K 8644. No significant differences were observed in CMG after intrathecal administration of T-type VGCC blocker TTA-P2. Additionally, immunofluorescence of the lumbosacral cord in control and SCI rats showed that the 5-HT2A receptor and Cav1.2 immunolabeling-positive neurons in the anterior horn of the lumbosacral cord were increased in SCI rats. Our study demonstrated that 5-HT2A/2C agonist 2,5-dimethoxy-4-iodophenyl-2-aminopropane hydrochloride may improve SCI-induced DSD by inhibiting the L-type voltage-gated calcium channel in lumbosacral cord motoneurons.

Changes and clinical significance of NLRP3 inflammasomes and related factors in patients with spinal fracture complicated with acute spinal cord injury

To investigate the changes and clinical significance of NOD like receptor protein 3 (NLRP3) inflammasomes and related factors in patients with spinal fractures complicated with acute spinal cord injury (SCI). Eighty-six spinal fracture patients complicated with acute SCI admitted to hospital from June 2019 to March 2022 were selected as SCI group, There were 48 males and 38 females, with an average age of (43.48±6.58) years old. And 100 healthy volunteers who underwent physical examination during the same time were selected as control group, including 56 males patients and 44 females patients, with an average age of (45.13±6.43) years old. Peripheral blood mononuclear cell (PBMC) were collected, and the mRNA expressions of NLRP3 and Caspase-1 were detected. Serum was collected and the levels of interleukin (IL)- 1β, IL-18 were detected. According to Frankel's grade, the SCI group was divided into complete injury patients and incomplete injury patients, and according to the Japanese Orthopedic Society (JOA) grade, the SCI group was divided into good prognosis group and poor prognosis group. The difference of NLRP3, Caspase-1, IL-1β, IL-18 among groups were compared, the influencing factors for poor prognosis in SCI patients was analyzed by Logistic regression. The mRNA expression levels of NLRP3 (1.41±0.33) and Caspase-1 (1.44±0.35) in PBMC and the levels of IL-1β(45.34±13.22) pg·ml-1, IL-18(40.95±8.77) pg·ml-1 in serum of SCI group were higher than those of the control group[(1.00±0.19), (1.00±0.16), (16.58±4.24) pg·ml-1, (12.57±3.68) pg·ml-1] (P<0.05). The mRNA expression levels of NLRP3(1.63±0.34) and Caspase-1 (1.67±0.27) in PBMC and the levels of IL-1β(51.09±11.10) pg·ml-1, IL-18 (47.65±7.93) pg·ml-1 in serum of patients with complete injury in the SCI group were higher than those of patients with incomplete injury [(1.31±0.27), (1.34±0.33), (42.85±13.36) pg·ml-1, (38.05±7.48) pg·ml-1](P<0.05). The mRNA expression levels of NLRP3 (1.66±0.31) and Caspase-1 (1.72±0.31)in PBMC and the levels of IL-1β(51.21±11.31) pg·ml-1, IL-18 (45.70±7.25) pg·ml-1 in serum, the proportion of complete injury(21 patients), and the proportion of spinal cord edema or bleeding of patients(15 patients) with poor prognosis in the SCI group were higher than those of patients with good prognosis[(1.28±0.26), (1.37±0.36), (42.79±13.25) pg·ml-1、(38.90±8.63) pg·ml-1, 5、20 cases](P<0.05). Complete injury and the mRNA expression of NLRP3 in PBMC were the influencing factors for poor prognosis in the SCI group (P<0.05). The activation of NLRP3 inflammasomes in patients with spinal fractures complicated with acute SCI is associated with worsening injury and poor prognosis, and NLRP3 expression can serve as a marker for evaluating prognosis.

Optical imaging detection of extracellular vesicles of miR-146 modified bone marrow mesenchymal stem cells promoting spinal cord injury repair

Bone Marrow mesenchymal Stem Cells (BMSCs) are considered as an important source of cells for regenerative medicine, In particular, Bone Marrow mesenchymal Stem Cells Exosomes (BMSCs-EXO) have the most significant effect in the treatment of Spinal Cord Injury (SCI), but the mechanism of action is still unknown. This study found that compared with other SCI groups, BMSCs-EXO loaded with miR-146a could significantly improve the functional recovery of the hind limbs of SCI rats. Hematoxylin and eosin (H&E) indicated that the lesion area of spinal cord injury was less, nissl staining indicated that the number of nissl bodies remained more; the mechanism may be through inhibiting the expression of IRAK1 and TRAF6, blocking the activation of NF-κB p65, reducing the expression of TNF-α, IL-1β and IL-6 inflammatory factors and oxidative stress, improving the SCI microenvironment, and promoting the repair of neural function. In general, we found that BMSCs-EXO loaded with miR-146a could reduce the inflammatory response and oxidative stress in SCI by inhibiting the activation of IRAK1/TRAF6/NF-κB p65 signaling pathway, and promote the recovery of neurological function in SCI rats.

Treadmill training improves neural function recovery in rats with spinal cord injury via JAK2/STAT3 signaling pathway and attenuating apoptosis.

To investigate the role of JAK2/STAT3 signaling pathway in neural function recovery in rats with spinal cord injury (SCI) after treadmill training. Sprague-Dawley rats were randomly divided into four groups: (a) sham group; (b) SCI group; (c) SCI+treadmill training group (SCI/TT); and (d) SCI/TT+AG490 group (a JAK2 inhibitor) ( n = 12). The 12 Sprague-Dawley rats in each group were randomly assigned into 1 st , 3 rd , 7 th , and 14 th day subgroups. The Basso-Beattie-Bresnahan (BBB) locomotor rating scale was used to assess the spinal cord function, and JAK2, STAT3, and IL-6 protein expressions in the rat spinal cord were evaluated by western blot. The level of cell apoptosis and expressions of apoptotic proteins were evaluated by TUNEL assay and immunohistochemistry, respectively. Rats in the SCI+TT group showed a significantly higher BBB score after SCI compared with the SCI group and the SCI/TT+AG490 group. Mechanistically, the JAK2/STAT3 signal pathway was immediately activated after SCI compared with sham group, and JAK2 and STAT3 were obviously upregulated when treadmill training was performed ( P < 0.05). Results of TUNEL assay showed that the apoptotic rate in SCI/TT was significantly lower than that in the SCI group and SCI/TT+AG490 group ( P < 0.05). Besides, the IL-6 expression in the SCI/TT group was significantly attenuated compared with the SCI group ( P < 0.05). Our results showed that physical treadmill training can enhance activation of JAK2/STAT3 signal pathway and attenuate apoptosis in the injured spinal cord, resulting in better functional recovery. These results underline the importance of synergistic treatment strategies for SCI.

Risk factors and prognosis of postoperative spinal cord injury in type A aortic dissection.

To investigate the risk factors and prognosis of spinal cord injury (SCI) after surgical procedure in type A aortic dissection (AAD). Between January 2013 and December 2021, a total of 1647 patients with AAD underwent surgical procedure. Postoperative SCI occurred in 58 patients, including 24 patients with paraplegia and 34 patients with paraparesis. Factors associated with SCI were identified through comparison between patients with and without SCI. The mean age was 48.8 ± 10.8 years for patients with SCI and 50.1 ± 12.1 years for those without SCI (P = 0.43), with a comparable gender distribution. Median numbers of intercostal and lumbar arteries with involvement were significantly higher in the SCI group (both P < 0.001). The highest (P = 0.033) and lowest (P = 0.001) levels of intraoperative mean arterial pressure (MAP) were significantly lower in the SCI group. Multivariable analysis revealed the number of segmental arteries involved (odds ratio = 1.14, 95% CI 1.08-1.20, P = 0.000), and the duration of hypothermic circulatory arrest (HCA) (odds ratio = 1.04, 95% CI 1.01-1.08, P = 0.042) was positively associated with the occurrence of SCI. Conversely, the lowest level of MAP was negatively associated with SCI (odds ratio = 0.98, 95% CI 0.96-0.99, P = 0.031). During the long-term follow-up, 14 patients with paraplegia needed a wheel chair, while only 1 patient with paraparesis needed one (P < 0.001). The risk of postoperative SCI increases when AAD patients experience segmental arteries involved, longer HCA duration and decreased intraoperative MAP during operation.

Silibinin promotes healing in spinal cord injury through anti-ferroptotic mechanisms.

Pre-clinical animal experiment. In this study, we investigated therapeutic effects of silibinin in a spinal cord injury (SCI) model. In SCI, loss of cells due to secondary damage mechanisms exceeds that caused by primary damage. Ferroptosis, which is iron-dependent non-apoptotic cell death, is shown to be influential in the pathogenesis of SCI. The study was conducted as an in vivo experiment using a total of 78 adult male/female Sprague Dawley rats. Groups were as follows: Sham, SCI, deferoxamine (DFO) treatment, and silibinin treatment. There were subgroups with follow-up periods of 24 h, 72 h, and 6 weeks in all groups. Malondialdehyde (MDA), glutathione (GSH), and Fe2+ levels were measured by spectrophotometry. Glutathione peroxidase-4 (GPX4), ferroportin (FPN), transferrin receptor (TfR1), and 4-hydroxynonenal (4-HNE)-modified protein levels were assessed by Western blotting. Functional recovery was assessed using Basso-Beattie-Bresnahan test. Silibinin achieved significant suppression in MDA and 4-HNE levels compared to the SCI both in 72-h and 6 weeks group (p < 0.05). GSH, GPX4, and FNP levels were found to be significantly higher in the silibinin 24 h, 72 h, and 6 weeks group compared to corresponding SCI groups (p < 0.05). Significant reduction in iron levels was observed in silibinin treated rats in 72 h and 6 weeks group (p < 0.05). Silibinin substantially suppressed TfR1 levels in 24 h and 72 h groups (p < 0.05). Significant difference among recovery capacities was observed as follows: Silibinin > DFO > SCI (p < 0.05). Impact of silibinin on iron metabolism and lipid peroxidation, both of which are features of ferroptosis, may contribute to therapeutic activity. Within this context, our findings posit silibinin as a potential therapeutic candidate possessing antiferroptotic properties in SCI model. Therapeutic agents capable of effectively and safely mitigating ferroptotic cell death hold the potential to be critical points of future clinical investigations.

Therapeutic effect and mechanism of piracetam for the treatment of spinal cord injury in rats through MAPK pathway

To explore mechanism of piracetam for the treatment of spinal cord injury in rats through mitogen-activated protein kinase (MAPK) pathway. Fifty-four healthy 6-week-old SD female rats with body weight of 80 to 100 g were divided into sham operation group, spinal cord injury group and piracetam group by random number table method, with 18 rats in each group. Spinal cord injury model was established in spinal cord injury group and piracetam group using percussion apparatus, while sham operation group did not damage spinal cord. Piracetam group was injected with piracetam injection through tail vein according to 5 ml·kg-1 standard, once a day for 3 days;the other two groups were injected with normal saline at the same dose, the same frequency and the same duration. The rats were sacrificed at 1, 3, and 7 days after surgery, and changes of Basso, Beattie and Bresnahan (BBB) locomotor rating scale was observed and compared. Enzyme-linked immunosorbent assay (ELISA) was used to detect spinal cord inflammatory factors, such as interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-1β (interleukin-1β), necrosis factor-α (IL-1β) and tumor necrosis factor-α (TNF-α);HE staining was used to observe morphological changes of rats with spinal cord injury, and immunohistochemistry was used to observe expression level of aquaporin 4 (AQP4). The activation of MAPK signaling pathway in spinal cord of rats after spinal cord injury was observed by western blotting (WB). BBB scores of sham operation group on 1, 3 and 7 day were 21 points. In spinal cord injury group, the scores were (1±1), (4±1) and (7±2);piracetam group was (1±1), (5±1), (9±2), respectively;the difference between spinal cord injury group and sham operation group was statistically significant (P<0.05). HE staining showed that no abnormality was found in sham operation group. In spinal cord injury group, bleeding and degeneration of spinal cord tissue appeared at 1 day after operation; flaky necrotic areas were appeared in spinal cord at 3 days after surgery, and spinal cord tissue began to slowly repair at 7 days after surgery. In piracetam group, the bleeding area was less than that of spinal cord injury group at 1 day after surgery;at 3 days after operation, the necrotic area was reduced and the range of nuclear disappearance was reduced; and the spinal cord began to recover slowly at 7 days after surgery. AQP4 staining of spinal cord of rats in sham operation group was weak at 1, 3 and 7 days after modeling, AQP4 staining was deepened and area increased in spinal cord injury group, AQP4 staining of piracetam group was lighter than that of spinal cord injury group, and the positive cells were slightly increased and the staining was slightly darker than that of sham operation group. At 1, 3 and 7 days, the level of IL-6, IL-10, IL-1β and TNF-α in spinal cord injury group were higher than those in sham operation group and piracetam group(P<0.05). Compared with spinal cord injury group, the area of spinal cord bleeding and necrosis were decreased by HE staining in piracetam group, and AQP4 staining was decreased by immunohistochemistry. WB results showed that P-ERK, P-JNK and P-P38 levels in spinal cord injury group at 3 days were higher than those in sham operation group and piracetam group(P<0.05). Piracetam not only showed significant effect in promoting motor function recovery after spinal cord injury, but also showed positive therapeutic potential in reducing lesion area, regulating AQP4 expression to reduce edema, and reducing inflammatory response by regulating MAPK signaling pathway.

Traumatic Cervical Spinal Cord Injury and Income and Employment Status

Spinal cord injury (SCI) causes drastic changes to an individual's physical health that may be associated with the ability to work. To estimate the association of SCI with individual earnings and employment status using national administrative health databases linked to income tax data. This was a retrospective, national, population-based cohort study of adults who were hospitalized with cervical SCI in Canada between January 2005 and December 2017. All acute care hospitalizations for SCI of adults ages 18 to 64 years were included. A comparison group was constructed by sampling from individuals in the injured cohort. Fiscal information from their preinjury years was used for comparison. The injured cohort was matched with the comparison group based on age, sex, marital status, province of residence, self-employment status, earnings, and employment status in the year prior to injury. Data were analyzed from August 2022 to January 2023. The first outcome was the change in individual annual earnings up to 5 years after injury. The change in mean yearly earnings was assessed using a linear mixed-effects differences-in-differences regression. Income values are reported in 2022 Canadian dollars (CAD $1.00 = US $0.73). The second outcome was the change in employment status up to 5 years after injury. A multivariable probit regression model was used to compare proportions of individuals employed among those who had experienced SCI and the paired comparison group of participants. A total of 1630 patients with SCI (mean [SD] age, 47 [13] years; 1304 male [80.0%]) were matched to patients in a preinjury comparison group (resampled from the same 1630 patients in the SCI group). The mean (SD) of preinjury wage earnings was CAD $46 000 ($48 252). The annual decline in individual earnings was CAD $20 275 (95% CI, -$24 455 to -$16 095) in the first year after injury and CAD $20 348 (95% CI, -$24 710 to -$15 985) in the fifth year after injury. At 5 years after injury, 52% of individuals who had an injury were working compared with 79% individuals in the preinjury comparison group. SCI survivors had a decrease in employment of 17.1 percentage points (95% CI, 14.5 to 19.7 percentage points) in the first year after injury and 17.8 percentage points (14.5 to 21.1 percentage points) in the fifth year after injury. In this study, SCI was associated with a decline in earnings and employment up to 5 years after injury for adults aged 18 to 64 years in Canada.

Delayed cerebrovascular reactivity in individuals with spinal cord injury in the right inferior parietal lobe: a breath-hold functional near-infrared spectroscopy study.

Cerebrovascular reactivity (CVR) reflects the ability of blood vessels to dilate or constrict in response to a vasoactive stimulus, and allows researchers to assess the brain's vascular health. Individuals with spinal cord injury (SCI) are at an increased risk for autonomic dysfunction in addition to cognitive impairments, which have been linked to a decline in CVR; however, there is currently a lack of brain-imaging studies that investigate how CVR is altered after SCI. In this study, we used a breath-holding hypercapnic stimulus and functional near-infrared spectroscopy (fNIRS) to investigate CVR alterations in individuals with SCI (n = 20, 14M, 6F, mean age = 46.3 ± 10.2 years) as compared to age- and sex-matched able-bodied (AB) controls (n = 25, 19M, 6F, mean age = 43.2 ± 12.28 years). CVR was evaluated by its amplitude and delay components separately by using principal component analysis and cross-correlation analysis, respectively. We observed significantly delayed CVR in the right inferior parietal lobe in individuals with SCI compared to AB controls (linear mixed-effects model, fixed-effects estimate = 6.565, Satterthwaite's t-test, t = 2.663, p = 0.008), while the amplitude of CVR was not significantly different. The average CVR delay in the SCI group in the right inferior parietal lobe was 14.21 s (sd: 6.60 s), and for the AB group, the average delay in the right inferior parietal lobe was 7.08 s (sd: 7.39 s). CVR delays were also associated with the duration since injury in individuals with SCI, in which a longer duration since injury was associated with a shortened delay in CVR in the right inferior parietal region (Pearson's r-correlation, r = -0.59, p = 0.04). This study shows that fNIRS can be used to quantify changes in CVR in individuals with SCI, and may be further used in rehabilitative settings to monitor the cerebrovascular health of individuals with SCI.

Dysregulated MiR-223-5p Modulates Inflammation and Oxidative Stress in Traumatic Spinal Cord Injury

ABSTRACT Aim This study aimed to evaluate the miR-223-5p expression in patients with spinal cord injury (SCI) and to determine its role in the pathogenesis of SCI. Methods The serum miR-223-5p levels were analyzed using quantitative real-time polymerase chain reaction. The diagnostic accuracy of miR-223-5p was evaluated using the receiving operating characteristic curves. LPS-induced PC12 cells were established as an in vitro inflammatory cell model. Cell apoptosis, inflammation and oxidative stress were examined. The SCI rat model was constructed to evaluate the effects of miR-223-5p on inflammatory response and motor function in rats. Results MiR-223-5p expression was upregulated in SCI patients. MiR-223-5p expression in the complete SCI group was significantly higher than that in incomplete SCI group. ROC analysis showed that miR-223-5p can distinguish SCI patients from healthy volunteers. In vitro experiments demonstrated that LPS upregulated apoptosis and inflammation in PC12 cells. Treatment with miR-223-5p inhibitor alleviated the changes in LPS-induced PC12 cells . Inhibition of miR-223-5p can alleviate the activation of inflammatory response and the effects of SCI on the motor function in rats. Conclusions MiR-223-5p is a potential diagnostic marker for SCI, and it can promote the SCI progression by regulating nerve cell survival, inflammation, and oxidative stress.