OBJECTIVES: Neuropathic pain (NP) is one of the most common forms of chronic pain, yet current treatment options are limited in effectiveness. Peripheral nerve injury activates spinal microglia, altering their inflammatory response and phagocytic functions, which contributes to the progression of NP. Most current research on NP focuses on microglial inflammation, with relatively little attention to their phagocytic function. Early growth response factor 2 (EGR2) has been shown to regulate microglial phagocytosis, but its specific role in NP remains unclear. This study aims to investigate how EGR2 modulates microglial phagocytosis and its involvement in NP, with the goal of identifying potential therapeutic targets. METHODS: Adult male Sprague-Dawley (SD) rats were used to establish a chronic constriction injury (CCI) model of the sciatic nerve. Pain behaviors were assessed on days 1, 3, 7, 10, and 14 post-surgery to confirm successful model induction. The temporal and spatial expression of EGR2 in the spinal cord was examined using real-time quantitative PCR (RT-qPCR), Western blotting, and immunofluorescence staining. Adeno-associated virus (AAV) was used to overexpress EGR2 in the spinal cord, and behavioral assessments were performed to evaluate the effects of EGR2 modulation of NP. CCI and lipopolysaccharide (LPS) models were established in animals and microglial cell lines, respectively, and changes in phagocytic activity were measured using RT-qPCR and fluorescent latex bead uptake assays. After confirming the involvement of microglial phagocytosis in NP, AAV was used to overexpress EGR2 in both in vivo and in vitro models, and phagocytic activity was further evaluated. Finally, eukaryotic transcriptome sequencing was conducted to screen differentially expressed mRNAs, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses to identify potential downstream effectors of EGR2. RESULTS: The CCI model successfully induced NP. Following CCI, EGR2 expression in the spinal cord was upregulated in parallel with NP development. Overexpression of EGR2 via spinal AAV injection enhanced microglial phagocytic activity and increased pain hypersensitivity in rats. Both animal and cellular models showed that CCI or LPS stimulation enhanced microglial phagocytosis, which was further amplified by EGR2 overexpression. Transcriptomic analysis of spinal cord tissues from CCI rats overexpressing EGR2 revealed upregulation of numerous genes associated with microglial phagocytosis and pain regulation. Among them, Lag3 emerged as a potential downstream target of EGR2. CONCLUSIONS EGR2 contributes to the maintenance of NP by enhancing microglial phagocytosis in the spinal dorsal horn.
Animals ; Microglia/metabolism* ; Phagocytosis/physiology* ; Rats, Sprague-Dawley ; Neuralgia/physiopathology* ; Early Growth Response Protein 2/metabolism* ; Male ; Rats ; Spinal Cord/metabolism* ; Sciatic Nerve/injuries*

OBJECTIVES: To investigate the effect of monotropein on motor function recovery of mice with spinal cord injury (SCI) and explore the underlying mechanism. METHODS: Forty-five adult female C57BL/6 mice were randomized equally into sham operation group, SCI group, and SCI group with daily intraperitoneal monotropein injection. The mice in the former two groups received daily saline injections. Motor function of the mice was evaluated using BMS scores, slant plate test, and footprint analyses. Pathological changes and neuronal counts in the spinal cord were observed using HE, LFB, and Nissl staining. The biological functions of monotropein were explored using GO and KEGG enrichment analyses. NeuN/cleaved caspase-3 immunofluorescence assay and Western blotting were used to detect neuronal apoptosis in the spinal cord of the mice. In cultured HT22 cells, the effect of monotropein on TNF-α-induced cell apoptosis was evaluated using TUNEL staining and Western blotting. In monotropein-treated HT22 cells and SCI mice, the changes in the PI3K/AKT pathway were examined, and the effect of a PI3K/AKT pathway activator (IGF-1) on HT22 cell apoptosis and motor function recovery of SCI mice were observed. RESULTS: SCI mice with monotropein treatment showed significantly improved motor functions with reduced SCI areas and increased myelin retention and neuron counts in the spinal cord. Bioinformatics analysis suggested a role of PI3K/AKT signaling pathway in mediating the anti-apoptotic effects of monotropein. In SCI mice, monotropein obviously reduced apoptotic neurons, decreased expressions of cleaved caspase-3 and Bax and increased Bcl-2 expression in the spinal cord. In HT22 cells, monotropein significantly inhibited TNF-α-induced apoptosis and PI3K/AKT pathway activation. Treatment with IGF-1 obviously increased apoptosis of HT22 cells and exacerbated locomotor dysfunction in SCI mice. CONCLUSIONS Monotropein promotes motor function recovery in SCI mice by reducing neuronal apoptosis possibly by inhibiting the PI3K/AKT signaling pathway.
Animals ; Spinal Cord Injuries/metabolism* ; Apoptosis/drug effects* ; Signal Transduction/drug effects* ; Mice, Inbred C57BL ; Mice ; Proto-Oncogene Proteins c-akt/metabolism* ; Female ; Phosphatidylinositol 3-Kinases/metabolism* ; Neurons/pathology* ; Recovery of Function

OBJECTIVES: To investigate the effect of orexin-A-mediated regulation of ionotropic glutamate receptors for promoting motor function recovery in rats with spinal cord injury (SCI). METHODS: Thirty-six newborn SD rats (aged 7-14 days) were randomized into 6 groups (n=6), including a normal control group, a sham-operated group, and 4 SCI groups with daily intrathecal injection of saline, DNQX, orexin-A, or orexin-A+DNQX for 3 consecutive days after PCI. Motor function of the rats were evaluated using blood-brain barrier (BBB) score and inclined plane test 1 day before and at 1, 3, and 7 days after SCI. For patch-clamp experiment, spinal cord slices from newborn rats in the control, sham-operated, SCI, and SCI+orexin groups were prepared, and ventral horn neurons were acutely isolated to determine the reversal potential and dynamic indicators of glutamate receptor-mediated currents under glutamate perfusion. RESULTS: At 3 and 7 days after SCI, the orexin-A-treated rats showed significantly higher BBB scores and grip tilt angles than those with other interventions. Compared with those treated with DNQX alone, the rats receiving the combined treatment with orexin and DNQX had significantly higher BBB scores and grip tilt angles on day 7 after PCI. In the patch-clamp experiment, the ventral horn neurons from SCI rat models exhibited obviously higher reversal potential and greater rise slope of glutamate current with shorter decay time than those from sham-operated and orexin-treated rats. CONCLUSIONS Orexin-A promotes motor function recovery in rats after SCI possibly by improving the function of the ionotropic glutamate receptors.
Animals ; Spinal Cord Injuries/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Receptors, Ionotropic Glutamate/metabolism* ; Recovery of Function/drug effects* ; Orexins/pharmacology* ; Male ; Female ; Animals, Newborn ; Neuropeptides/pharmacology* ; Intracellular Signaling Peptides and Proteins/pharmacology*

Demyelination and remyelination play key roles in spinal cord injury (SCI), affecting the recovery of motor and sensory functions. Research in rodent models is extensive, but the study of these processes in non-human primates is limited. Therefore, our goal was to thoroughly study the histological features of demyelination and remyelination after contusion injury of the cervical spinal cord in Macaca fascicularis. In a previous study, we created an SCI model in M. fascicularis by controlling the contusion displacement. We used Eriochrome Cyanine staining, immunohistochemical analysis, and toluidine blue staining to evaluate demyelination and remyelination. The results showed demyelination ipsilateral to the injury epicenter both rostrally and caudally, the former mainly impacting sensory pathways, while the latter primarily affected motor pathways. Toluidine blue staining showed myelin loss and axonal distension at the injury site. Schwann cell-derived myelin sheaths were only found at the center, while thinner myelin sheaths from oligodendrocytes were seen at the center and surrounding areas. Our study showed that long-lasting demyelination occurs in the spinal cord of M. fascicularis after SCI, with oligodendrocytes and Schwann cells playing a significant role in myelin sheath formation at the injury site.
Animals ; Spinal Cord Injuries/physiopathology* ; Demyelinating Diseases/etiology* ; Remyelination/physiology* ; Macaca fascicularis ; Disease Models, Animal ; Myelin Sheath/pathology* ; Oligodendroglia/pathology* ; Schwann Cells/pathology* ; Female ; Spinal Cord/pathology* ; Axons/pathology*

BACKGROUND: Spinal cord injury (SCI) survivors often experience constipation, which contributes to a reduced sense of well-being and a lower quality of life. Acupressure offers a non-pharmacological and non-invasive alternative therapy for treating constipation. OBJECTIVE: This study examined the effects of home-based acupressure on constipation and subjective well-being among SCI survivors. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: This randomized controlled trial randomly assigned 80 adults from Hong Kong with SCI to two study groups. Using a video demonstration filmed by a registered traditional Chinese medicine practitioner, the intervention group performed home-based acupressure (self-administered or caregiver-assisted) twice daily, 15 min/session, for 10 consecutive days. The control group performed manual light touching of the abdomen with the same frequency and duration as the intervention group. Both groups received defecation education through a structured booklet. MAIN OUTCOMES MEASURES: The primary outcome was constipation severity. Secondary outcomes included bowel habits, psychological well-being, and quality of life. Focus group interviews were conducted after the intervention to collect subjective feedback from participants. RESULTS: Significant group-by-time interaction effects on constipation severity (P = 0.005) and quality of life (P = 0.001) revealed that home-based acupressure produced better results than the control. These treatment effects persisted at the one-month follow-up and continued to have a large effect size (Cohen's d > 0.8). Compared to the control group, the acupressure group also had improvements in anxiety (Cohen's d = 0.69) and depression (Cohen's d = 0.72) at the end of the intervention period. Three qualitative categories were identified from the focus group interviews: improvements in bowel function and management; reduced psychological distress following relief from constipation; and acceptability of home-based acupressure. CONCLUSION: Acupressure effectively relieves constipation, enhances psychological well-being, and improves quality of life in people with SCI. These data provide novel evidence supporting the use of home-based acupressure as an acceptable and effective therapy for treating constipation after SCI. TRIAL REGISTRATION ClinicalTrials.gov (NCT05558657). Please cite this article as: Li MQ, Li Y, Lam W, Yeung WF, Ho YS, Li JY, Sun TC, Yuen S, Hu YL, Yorke J. Home-based acupressure for managing constipation and subjective well-being in spinal cord injury survivors: A randomized controlled trial. J Integr Med. 2025; 23(6):660-669.
Humans ; Acupressure/methods* ; Constipation/psychology* ; Male ; Female ; Spinal Cord Injuries/complications* ; Middle Aged ; Adult ; Quality of Life ; Aged

OBJECTIVE: To observe the effects of moxibustion at "Shenque" (CV8) on urodynamics and the expression of brain-derived neurotrophic factor (BDNF) and immediate early gene (c-fos) in pontine micturition center (PMC), periaqueductal gray (PAG), medial prefrontal cortex (mPFC) of neurogenic bladder (NB) rats after spinal cord injury. METHODS: Twenty-four SPF female SD rats were randomly divided into a sham-operation group (6 rats) and a modeling group (18 rats). In the modeling group, T₉ complete spinal cord transection method was used to establish a neurogenic detrusor overactivity model, and the 12 rats with successful modeling were randomized into a model group and a moxibustion group, with 6 rats in each group. The rats in the moxibustion group were treated with ginger/salt-insulated moxibustion at "Shenque" (CV8), and 4 consecutive moxa cones were delivered in one intervention. Moxibustion was operated once daily and for 14 days. After intervention completion, the urodynamic indexes of rats in each group were detected. Fluorescence quantitative PCR was used to detect the mRNA expression of BDNF and c-fos in PMC, PAG and mPFC in rats. Western blot was used to detect the protein expression of BDNF and c-fos in PMC, PAG and mPFC. RESULTS: The rats in the sham-operation group did not show phasic detrusor contraction during bladder filling. Compared with the model group, the frequency and amplitude of the phasic detrusor contraction were reduced 5 min before urine leakage in the rats of the moxibustion group (P<0.05), and the duration of the first phasic detrusor contraction during bladder filling was prolonged (P<0.05). Compared with the sham-operation group, the mRNA and protein expression of BDNF and c-fos in PMC, PAG and mPFC increased in the model group (P<0.05). Compared with the model group, the mRNA and protein expression of BDNF and c-fos in PMC, PAG and mPFC decreased in the moxibustion group (P<0.05). CONCLUSION Moxibustion at "Shenque" (CV8) can improve the phasic contraction during bladder filling in NB rats after spinal cord injury, possibly by down-regulating the mRNA and protein expression of BDNF and c-fos in PMC, PAG, and mPFC.
Animals ; Moxibustion ; Female ; Rats ; Brain-Derived Neurotrophic Factor/metabolism* ; Rats, Sprague-Dawley ; Acupuncture Points ; Spinal Cord Injuries/metabolism* ; Urinary Bladder, Neurogenic/etiology* ; Proto-Oncogene Proteins c-fos/metabolism* ; Humans ; Urinary Bladder/physiopathology* ; Brain/metabolism* ; Urination

OBJECTIVE: To observe the clinical effect of acupuncture and moxibustion combined with umbilical therapy on anxiety and depression in patients with neurogenic bladder (NB) after spinal cord injury (SCI). METHODS: Thirty cases of NB after SCI with anxiety and depression were selected and treated with acupuncture and moxibustion combined with umbilical therapy. Acupuncture was applied at Baihui (GV20), Yintang (GV24⁺), Sanyinjiao (SP6), Shenmen (HT7), Hegu (LI4), Taichong (LR3), once a day, continuous treatment for 4 weeks. Ginger moxibustion was applied at the bladder meridian of foot taiyang and governor vessel, once a day, continuous treatment for 4 weeks. In treatment of umbilical therapy, Chaihu (Radix Bupleuri), Yujin (Radix Curcumae), Rougui (Cortex Cinnamomi) were ground and mixed with the same amount of honey, put into the application, and the application was placed on the navel after filling the navel with fine salt, once a day for 4 weeks. Hamilton anxiety scale (HAMA) score, Hamilton depression scale (HAMD) score, urodynamic indexes (maximum urinary flow rate [Qmax], maximum detrusor pressure [Pdet-max], residual urine volume [RUV]), neurogenic bladder symptom score (NBSS), urinary symptom distress scale (USDS) score were compared before and after treatment, and the clinical efficacy was evaluated. RESULTS: After treatment, the scores of HAMA, HAMD, NBSS, USDS and RUVwere lower than those before treatment (P<0.05), and Qmax and Pdet-max were higher than those before treatment (P<0.05). The total effective rate was 93.3 (28/30). CONCLUSION Acupuncture and moxibustion combined with umbilical therapy can effectively relieve anxiety and depression symptoms, improve urination disorders in patients with NB after SCI.
Humans ; Moxibustion ; Male ; Female ; Adult ; Middle Aged ; Acupuncture Therapy ; Spinal Cord Injuries/psychology* ; Depression/etiology* ; Anxiety/etiology* ; Urinary Bladder, Neurogenic/etiology* ; Young Adult ; Aged ; Combined Modality Therapy ; Acupuncture Points

OBJECTIVE: To observe the effects of ultrasound-guided foraminal electroacupuncture on neuronal apoptosis and motor function in rats with spinal cord injury (SCI), and to explore the potential underlying mechanisms. METHODS: Thirty-six SPF-grade Sprague-Dawley rats were randomly assigned to a sham operation group, a model group, and an ultrasound-guilded electroacupuncture group (electroacupuncture group), with 12 rats in each group. In the sham operation group, the spinal cord was exposed and then the incision was sutured without contusion. In the other two groups, SCI models were established using a modified Allen's impact method. On days 1, 3, 7, and 14 after modeling, the electroacupuncture group received electroacupuncture intervention at the T₉/T₁₀ and T₁₀/T₁₁ intervertebral foramen under ultrasound guidance, avoiding spinal cord injury. Stimulation parameters were dense-disperse wave at 2 Hz/100 Hz and 1-2 mA for each session. Following interventions on days 1, 3, 7, and 14, the Basso-Beattie-Bresnahan (BBB) score was assessed; the inclined plane test was used to assess hindlimb grip strength in rats. After the intervention, HE staining was used to observe spinal cord morphology; TUNEL staining was used to detect neuronal apoptosis; ELISA was used to measure the serum levels of interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha (TNF-α); Western blot was used to analyze the protein expression of Wnt-4, β-catenin, c-Myc, Bax, Bcl-2, and NeuN in spinal tissue; quantitative real-time PCR was used to detect the mRNA expression of Wnt-4, β-catenin, c-Myc, Bax, Bcl-2, and NeuN. RESULTS: Compared with the sham operation group, the model group showed significantly reduced BBB scores (P<0.05), and reduced inclined plane angles (P<0.05) at all time points. Compared with the model group, the electroacupuncture group exhibited increased BBB scores on days 3, 7, and 14 (P<0.05), and higher inclined plane angles on days 1, 3, 7, and 14 (P<0.05). Compared with the sham operation group, the model group showed disorganized spinal cord structure with increased inflammatory cells and necrotic neurons, higher number of apoptotic neurons in spinal tissue (P<0.05), elevated serum IL-6, IL-1β, and TNF-α levels (P<0.05), increased protein and mRNA expression of Wnt-4, β-catenin, c-Myc, and Bax (P<0.05), and decreased protein and mRNA expression of Bcl-2 and NeuN in spinal tissue (P<0.05). Compared with the model group, the electroacupuncture group had fewer inflammatory cells and apoptotic neurons in spinal tissue (P<0.05), reduced serum IL-6, IL-1β, and TNF-α levels (P<0.05), increased protein and mRNA expression of Wnt-4, β-catenin, Bcl-2, and NeuN (P<0.05), and decreased protein and mRNA expression of c-Myc and Bax in spinal tissue (P<0.05). CONCLUSION Ultrasound-guided foraminal electroacupuncture could improve motor function in rats with SCI, potentially by regulating the expression of molecules related to the Wnt-4/β-catenin signaling pathway to inhibit neuronal apoptosis and inflammatory responses.
Animals ; Electroacupuncture/methods* ; Spinal Cord Injuries/physiopathology* ; Rats, Sprague-Dawley ; Rats ; Wnt Signaling Pathway ; Male ; Humans ; Female ; beta Catenin/metabolism* ; Apoptosis ; Ultrasonography ; Tumor Necrosis Factor-alpha/genetics* ; Spinal Cord/metabolism*

Clinical trials have demonstrated that kilohertz-frequency transcutaneous spinal cord stimulation (TSCS) can be used to facilitate the recovery of sensory-motor function for patients with spinal cord injury, whereas the neural mechanism of TSCS is still undetermined so that the choice of stimulation parameters is largely dependent on the clinical experience. In this paper, a finite element model of transcutaneous spinal cord stimulation was used to calculate the electric field distribution of human spinal cord segments T ₁₂ to L ₂, whereas the activation thresholds of spinal fibers were determined by using a double-cable neuron model. Then the variation of activation thresholds was obtained by varying the carrier waveform, the interphase delay, the modulating frequency, and the modulating pulse width. Compared with the sinusoidal carrier, the usage of square carrier could significantly reduce the activation threshold of dorsal root (DR) fibers. Moreover, the variation of activation thresholds was no more than 1 V due to the varied modulating frequency and decreases with the increased modulating pulse width. For a square carrier at 10 kHz modulated by rectangular pulse with the frequency of 50 Hz and the pulse width of 1 ms, the lowest activation thresholds of DR fibers and dorsal column fibers were 27.6 V and 55.8 V, respectively. An interphase delay of 5 μs was able to reduce the activation thresholds of the DR fibers to 20.1 V. The simulation results can lay a theoretical foundation on the selection of TSCS parameters in clinical trials.
Humans ; Spinal Cord Stimulation/methods* ; Nerve Fibers/physiology* ; Finite Element Analysis ; Spinal Cord/physiology* ; Computer Simulation ; Spinal Cord Injuries/physiopathology* ; Lumbosacral Region ; Lumbar Vertebrae ; Transcutaneous Electric Nerve Stimulation/methods* ; Models, Neurological

OBJECTIVE: To investigate the effects of removing microglia from spinal cord on nerve repair and functional recovery after spinal cord injury (SCI) in mice. METHODS: Thirty-nine 6-week-old female C57BL/6 mice were randomly divided into control group ( n=12), SCI group ( n=12), and PLX3397+SCI group ( n=15). The PLX3397+SCI group received continuous feeding of PLX3397, a colony-stimulating factor 1 receptor inhibitor, while the other two groups were fed a standard diet. After 14 days, both the SCI group and the PLX3397+SCI group were tested for ionized calcium binding adapter molecule 1 (Iba1) to confirm that the PLX3397+SCI group had completely depleted the spinal cord microglia. The SCI model was then prepared by clamping the spinal cord in both the SCI group and the PLX3397+SCI group, while the control group underwent laminectomy. Preoperatively and at 1, 3, 7, 14, 21, and 28 days postoperatively, the Basso Mouse Scale (BMS) was used to assess the hind limb function of mice in each group. At 28 days, a footprint test was conducted to observe the gait of the mice. After SCI, spinal cord tissue from the injury site was taken, and Iba1 immunofluorescence staining was performed at 7 days to observe the aggregation and proliferation of microglia in the spinal cord. HE staining was used to observe the formation of glial scars at the injury site at 28 days; glial fibrillary acidic protein (GFAP) immunofluorescence staining was applied to astrocytes to assess the extent of the injured area; neuronal nuclei antigen (NeuN) immunofluorescence staining was used to evaluate neuronal survival. And 5-hydroxytryptamine (5-HT) immunofluorescence staining was performed to assess axonal survival at 60 days. RESULTS: All mice survived until the end of the experiment. Immunofluorescence staining revealed that the microglia in the spinal cord of the PLX3397+SCI group decreased by more than 95% compared to the control group after 14 days of continuous feeding with PLX3397 ( P<0.05). Compared to the control group, the BMS scores in the PLX3397+SCI group and the SCI group significantly decreased at different time points after SCI ( P<0.05). Moreover, the PLX3397+SCI group showed a further decrease in BMS scores compared to the SCI group, and exhibited a dragging gait. The differences between the two groups were significant at 14, 21, and 28 days ( P<0.05). HE staining at 28 days revealed that the SCI group had formed a well-defined and dense gliotic scar, while the PLX3397+SCI group also developed a gliotic scar, but with a more blurred and loose boundary. Immunofluorescence staining revealed that the number of microglia near the injury center at 7 days increased in the SCI group than in the control group, but the difference between groups was not significant ( P>0.05). In contrast, the PLX3397+SCI group showed a significant reduction in microglia compared to both the control and SCI groups ( P<0.05). At 28 days after SCI, the area of spinal cord injury in the PLX3397+SCI group was significantly larger than that in SCI group ( P<0.05); the surviving neurons significantly reduced compared with the control group and SCI group ( P<0.05). The axonal necrosis and retraction at 60 days after SCI were more obvious. CONCLUSION The removal of microglia in the spinal cord aggravate the tissue damage after SCI and affecte the recovery of motor function in mice, suggesting that microglia played a neuroprotective role in SCI.
Animals ; Spinal Cord Injuries/surgery* ; Microglia/pathology* ; Female ; Mice ; Mice, Inbred C57BL ; Nerve Regeneration/drug effects* ; Spinal Cord/pathology* ; Pyrroles/administration & dosage* ; Aminopyridines/administration & dosage* ; Recovery of Function ; Disease Models, Animal ; Calcium-Binding Proteins/metabolism* ; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors* ; Microfilament Proteins/metabolism* ; Glial Fibrillary Acidic Protein/metabolism*