Management of acute traumatic spinal cord injuries

Spinal Cord Injury in the 21st Century Part I: A New Demographic

BACKGROUND

Guidelines for the management of acute spinal cord injury are based on a young age group suffering spinal fracture dislocations caused by high-impact trauma. The purpose of this study was to characterize our recent cervical spinal cord injury (cSCI) experience and compare it to this traditional demographic. We hypothesized that most cSCI patients now fall outside the scope of published guideline principles.

METHODS

Cross-sectional cohort study. A detailed review was performed of cSCI patients admitted to our level 1 trauma institution over a 12-month period identifying demographics, injury types, and coded diagnoses cross-referenced from multiple archival systems RESULTS: Fifty-one patients with cSCI from blunt trauma were identified over the 1-year study period of which 82% did not have a spinal fracture or dislocation. cSCI patients without fracture/dislocation were older (mean age 62), had low-impact injuries (93%), and lower American Spinal Injury Association grades (98%). Patients with fracture/dislocation were younger (mean age 48), had high-impact injuries (77%), and higher American Spinal Injury Association grades (66%). Ninety-eight percent of our cSCI patients without fracture/dislocation presented with sensory and motor changes preferentially involving hands and arms in contrast to 11% of patients with fracture dislocation (P < 00001).

CONCLUSIONS

cSCI patients without fracture/dislocation now represent the large majority of spinal cord injuries at our level I trauma center. The demographic is most consistent with central cord syndrome, implicating unique pathophysiology and natural history. Extrapolation of management principles from previous guideline efforts is not intuitively generalizable to this patient population.

Spinal Cord Injury in the 21st Century Part II: Deficiencies in Data

BACKGROUND

In Part I of this series we identified spinal cord injury without fracture or dislocation (SCIwoFD) as having become the most common type of spinal cord injury at our level I trauma center. The purpose of this paper was to examine two databases, one local and one national, to determine whether this population could be discovered using traditional search techniques.

METHODS

We analyzed ICD-10 codes applied by our institution to SCIwoFD patients identified in Part I for accuracy and appropriateness. Concurrently, we queried the National Inpatient Sample (NIS) database between 2015 and 2019 to identify an anticipated increase in SCIwoFD patients compared to patients with more traditional spinal cord injury (SCI) associated with fracture/dislocation.

RESULTS

The most common ICD-10 diagnosis provided for SCIwoFD patients at our institution was coded as cervicalgia (33%) followed by cervical spinal stenosis (21%). Five percent were coded for myelopathy, while central cord syndrome was coded in only 2%. Within the NIS, SCIwoFD was reported in only 15% of patients in sharp contrast to 82% of our own patients (P < 0.00001). Conversely, SCI associated with fracture/dislocation comprised 85% of all reported NIS cSCIs holding steady at this level during the study period, as did central cord syndrome (7%) and traumatic spondylopathy (1%).

CONCLUSIONS

Neither our institutional database nor the NIS allows for appropriate identification of patients suffering SCIwoFD. Properly constructed SCI-specific registries are likely to provide the only opportunity from which to establish best practice parameters for this new 21st-century demographic of SCI.

Diagnostic accuracy of an artificial intelligence algorithm versus radiologists for fracture detection on cervical spine CT

OBJECTIVES

To compare diagnostic accuracy of a deep learning artificial intelligence (AI) for cervical spine (C-spine) fracture detection on CT to attending radiologists and assess which undetected fractures were injuries in need of stabilising therapy (IST).

METHODS

This single-centre, retrospective diagnostic accuracy study included consecutive patients (age ≥18 years; 2007-2014) screened for C-spine fractures with CT. To validate ground truth, one radiologist and three neurosurgeons independently examined scans positive for fracture. Negative scans were followed up until 2022 through patient files and two radiologists reviewed negative scans that were flagged positive by AI. The neurosurgeons determined which fractures were ISTs. Diagnostic accuracy of AI and attending radiologists (index tests) were compared using McNemar.

RESULTS

Of the 2368 scans (median age, 48, interquartile range 30-65; 1441 men) analysed, 221 (9.3%) scans contained C-spine fractures with 133 IST. AI detected 158/221 scans with fractures (sensitivity 71.5%, 95% CI 65.5-77.4%) and 2118/2147 scans without fractures (specificity 98.6%, 95% CI 98.2-99.1). In comparison, attending radiologists detected 195/221 scans with fractures (sensitivity 88.2%, 95% CI 84.0-92.5%, p < 0.001) and 2130/2147 scans without fracture (specificity 99.2%, 95% CI 98.8-99.6, p = 0.07). Of the fractures undetected by AI 30/63 were ISTs versus 4/26 for radiologists. AI detected 22/26 fractures undetected by the radiologists, including 3/4 undetected ISTs.

CONCLUSION

Compared to attending radiologists, the artificial intelligence has a lower sensitivity and a higher miss rate of fractures in need of stabilising therapy; however, it detected most fractures undetected by the radiologists, including fractures in need of stabilising therapy. Clinical relevance statement The artificial intelligence algorithm missed more cervical spine fractures on CT than attending radiologists, but detected 84.6% of fractures undetected by radiologists, including fractures in need of stabilising therapy.

KEY POINTS

The impact of artificial intelligence for cervical spine fracture detection on CT on fracture management is unknown. The algorithm detected less fractures than attending radiologists, but detected most fractures undetected by the radiologists including almost all in need of stabilising therapy. The artificial intelligence algorithm shows potential as a concurrent reader.

Cerebrospinal Fluid Drainage in Patients with Acute Spinal Cord Injury: A Multi-Center Randomized Controlled Trial

OBJECTIVE

The secondary phase of spinal cord injury (SCI) is characterized by ischemic injury. Spinal cord perfusion pressure (SCPP), calculated as the difference between mean arterial pressure (MAP) and intrathecal pressure (ITP), has arisen as a therapeutic target for improving outcomes. Cerebrospinal fluid drainage (CSFD) may reduce ITP and thereby increase SCPP. Randomized controlled trial to evaluate the safety and feasibility of CSFD to improve SCPP and outcomes after acute SCI.

METHODS

Inclusion criteria included acute cervical SCI within 24 hours of presentation. All patients received lumbar drain placement and appropriate decompressive surgery. Patients randomized to the control group received MAP elevation only. Patients in the experimental group received MAP elevation and CSFD to achieve ITP <10 mmHg for 5 days. ITP and MAP were recorded hourly. Adverse events were documented and patients underwent functional assessments at enrollment, 72 hours, 90 days, and 180 days post-injury.

RESULTS

Eleven patients were enrolled; 4 were randomized to receive CSFD. CSFD patients had a mean ITP of 5.3 ± 2.5 mmHg versus. 15 ± 3.0 mmHg in the control group. SCPP improved significantly, from 77 ± 4.5 mmHg in the control group to 101 ± 6.3 mmHg in the CSFD group (P < 0.01). Total motor scores improved by 15 ± 8.4 and 57 ± 24 points in the control and CSFD groups, respectively, over 180 days. No adverse events were attributable to CSFD.

CONCLUSIONS

CSFD is a safe, effective mechanism for reducing ITP and improving SCPP in the acute period post-SCI. The favorable safety profile and preliminary efficacy should help drive recruitment in future studies.

Treatment of Acute Spinal Cord Injuries: A Survey Among Iberolatinoamerican Spine Surgeons - Part 1: Use of High-Dose Corticosteroids

Objective  The aim of the present study was to evaluate the current practice of using of methylprednisolone sodium succinate (MPSS) in acute spinal cord Injuries (ASCIs) among spine surgeons from Iberolatinoamerican countries. Methods  A descriptive cross-sectional study design as a survey was conducted. A questionnaire composed of 2 sections, one on demographic data regarding the surgeons and MPSS administration, was sent by email to members of the Sociedad Ibero Latinoamericana de Columna (SILACO, in the Spanish acronym) and associated societies. Results  A total of 182 surgeons participated in the study: 65.4% (119) orthopedic surgeons and 24.6% (63) neurosurgeons. Sixty-nine (37.9%) used MPSS in the initial management of ASCIs. There were no significant differences between countries ( p  = 0.451), specialty ( p  = 0.352), or surgeon seniority ( p  = 0.652) for the use of corticosteroids in the initial management of ASCIs. Forty-five (65.2%) respondents reported using an initial high-dose bolus (30 mg/Kg) followed by a perfusion (5.4 mg/kg/h). Forty-six (66.7%) surgeons who used MPSS only prescribed it if the patients presented within 8 hours of the ASCI. Most of the surgeons (50.7% [35]) administered high-dose corticosteroids because of the conviction that it has clinal benefits and improves neurological recovery. Conclusion  Results from the present survey show that MPSS use in ASCI is not widespread within spine surgeons and that the controversy regarding its use remains unresolved. This is probably due to the low level of evidence of the available data, to variations over the years, to inconsistencies in acute care protocols, and to health service pathways.

Early versus late surgical intervention for cervical spinal cord injury: A protocol for systematic review and meta-analysis

BACKGROUND

Acute traumatic cervical spinal cord injury (SCI) is a catastrophic event with substantial physical, emotional, and economic burdens to patients, families, and society. Spinal cord decompression is recommended for the treatment of acute SCI. However, the optimal surgical timing remains controversial. Therefore, we perform a protocol for systematic review and meta-analysis to compare the efficacy of early and late surgical intervention for acute SCI.

METHODS

This systematic review and meta-analysis follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols statement, which have been registered in advance in the International prospective register of systematic reviews (registration number: CRD42023397592). We will search the following databases for randomized controlled trials: the Cochrane Skin Group Trials Register, MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database, Chinese Medical Current Content, and China National Knowledge Infrastructure. The risk of bias of the included studies will be appraised using the Cochrane Collaboration tool for randomized controlled trials. Statistical analysis will be performed using IBM SPSS Statistics (Armonk, NY).

RESULT

The results of this systematic review will be published in a peer-reviewed journal.

CONCLUSION

This systematic review will provide evidence regarding the optimal timing for spinal cord decompression in patients with acute SCI.

Effectiveness of different surgical methods in the treatment of acute central cord syndrome without fractures and dislocations of the cervical spine

BACKGROUND

Acute central cord syndrome (ACCS) without fractures or dislocations is the most common form of incomplete spinal cord injury.

OBJECTIVE

To evaluate the effectiveness of different surgical methods in the treatment of acute central cord syndrome without fractures or dislocations of the cervical spine.

METHODS

A total of 164 patients with ACCS without fracture or dislocation of the cervical spine treated in our hospital from May 2012 to October 2019 were recruited and assigned to study group A and study group B according to different treatment modalities, with 82 cases in each group. Study group A underwent anterior cervical discectomy and fusion, and study group B was treated with posterior cervical laminectomy. The American Spinal Injury Association (ASIA) classification and motor scores of all cases at admission and at discharge were recorded, and the treatment outcomes of the two groups were compared.

RESULTS

No significant differences were found in the ASIA classification and ASIA motor scores between the two groups at admission (P> 0.05). One year after surgery, the ASIA motor scores and sensory scores were not statistically significant between the two groups (P> 0.05) but showed significant improvement compared to the preoperative scores (P< 0.05).

CONCLUSION

Both anterior cervical discectomy and fusion and posterior cervical laminectomy can improve the ASIA classification, ASIA motor scores, and sensory scores of ACCS patients without fractures or dislocations of the cervical spine. Therefore, surgical methods should be adopted based on the patients' conditions.

Endoplasmic Reticulum Stress Causing Apoptosis in a Mouse Model of an Ischemic Spinal Cord Injury

A spinal cord injury (SCI) is the devastating trauma associated with functional deterioration due to apoptosis. Most laboratory SCI models are generated by a direct impact on an animal's spinal cord; however, our model does not involve the direct impact on the spinal cord. Instead, we use a clamp compression to create an ischemia in the descending aortas of mice. Following the success of inducing an ischemic SCI (ISCI), we hypothesized that this model may show apoptosis via an endoplasmic reticulum (ER) stress pathway. This apoptosis by the ER stress pathway is enhanced by the inducible nitric oxide synthase (iNOS). The ER is used for the protein folding in the cell. When the protein folding capacity is overloaded, the condition is termed the ER stress and is characterized by the accumulation of misfolded proteins inside the ER lumen. The unfolded protein response (UPR) signaling pathways that deal with the ER stress response then become activated. This UPR activates the three signal pathways that are regulated by the inositol-requiring enzyme 1α (IRE1α), the activating transcription factor 6 (ATF6), and the protein kinase RNA-like ER kinase (PERK). IRE1α and PERK are associated with the expression of the apoptotic proteins. Apoptosis caused by an ISCI is assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) test. An ISCI also reduces synaptophysin and the neuronal nuclear protein (NeuN) in the spinal cord. In conclusion, an ISCI increases the ER stress proteins, resulting in apoptosis in neuronal cells in the spinal cord.

Chasing the Cup: A Comprehensive Review of Spinal Cord Injuries in Hockey

Ice hockey is a high-speed sport with a high rate of associated injury, including spinal cord injury (SCI). The incidence of hockey-related SCI has increased significantly in more recent years. A comprehensive literature search was conducted with the PubMed, Medline, Google Scholar, and Web of Science databases using the phrases “hockey AND spinal cord injuries” to identify relevant studies pertaining to hockey-related SCIs, equipment use, anatomy, and biomechanics of SCI, injury recognition, and return-to-play guidelines.

Fifty-three abstracts and full texts were reviewed and included, ranging from 1983 to 2021. The proportion of catastrophic SCIs is high when compared to other sports. SCIs in hockey occur most commonly from a collision with the boards due to intentional contact resulting in axial compression, as well as flexion-related teardrop fractures that lead to spinal canal compromise and neurologic injury. Public awareness programs, improvements in equipment, and rule changes can all serve to minimize the risk of SCI.

Hockey has a relatively high rate of associated SCIs occurring most commonly due to flexion-distraction injuries from intentional contact. Further investigation into equipment and hockey arena characteristics as well as future research into injury recognition and removal from and return to play is necessary.

Caring for patients with a traumatic spinal cord injury

ABSTRACT

The physical, emotional, and financial impact of a traumatic spinal cord injury (TSCI) can be devastating. This article discusses the pathophysiology of TSCI, medical and surgical management during the acute and subacute phases of injury, and nursing care for patients with TSCI.

Traumatic Brown-Séquard syndrome: modern reminder of a neurological injury

Brown-Séquard syndrome (BSS) presents as an ipsilateral loss of motor function, proprioception and vibratory sensation accompanied by contralateral pain and temperature loss two to three levels below the level of the injury. It is one of the syndromes associated with incomplete transection of the spinal cord. Classic BSS is rare as most patients present with mixed neurological deficits related to damage of the spinal cord and surrounding structures. BSS remains prevalent in areas with high trauma burden, where assaults with sharp weapons are common. We present the case of a man aged 38 years who sustained a stab injury to the left back. BSS was diagnosed. He underwent removal of the weapon in the operating room and had an uneventful recovery to near baseline functional level after a course of rehabilitation. Despite being a rare aetiology, BSS continues to be an excellent reminder to trauma providers of the anatomy and physiology of neuroanatomical tracts.

LncRNA H19 Regulates Lipopolysaccharide (LPS)-Induced Apoptosis and Inflammation of BV2 Microglia Cells Through Targeting miR-325-3p/NEUROD4 Axis

Spinal cord injury (SCI) is a devastating traumatic event worldwide. Work from the past decade has highlighted the key involvement of long non-coding RNAs (lncRNAs) in SCI. Nevertheless, the molecular action of lncRNA H19 in SCI is still not fully understood. The levels of H19, microRNA (miR)-325-3p, and neuronal differentiation 4 (NEUROD4) were determined by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Flow cytometry was performed to assess cell apoptosis. The levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), and IL-6 were detected using the enzyme-linked immunosorbent assay (ELISA). Targeted relationships among H19, miR-325-3p, and NEUROD4 were confirmed by dual-luciferase reporter, RNA immunoprecipitation (RIP), or RNA pull-down assays. Our data showed that H19 level was overexpressed in lipopolysaccharide (LPS)-treated BV2 cells. H19 silencing alleviated LPS-evoked cell apoptosis and inflammation. Mechanistically, H19 in BV2 cells directly targeted miR-325-3p, and NEUROD4 was a direct target of miR-325-3p. Moreover, miR-325-3p was a functional target of H19 in regulating cell apoptosis and inflammation induced by LPS. Enforced expression of miR-325-3p relieved LPS-evoked cell apoptosis and inflammation through reducing NEUROD4. Furthermore, H19 in BV2 cells regulated NEUROD4 expression through targeting miR-325-3p. Our results identified that the silencing of H19 attenuated LPS-evoked microglia cell apoptosis and inflammation after SCI at least partially through targeting the miR-325-3p/NEUROD4 axis, highlighting a novel approach for SCI management.

Emergency Management of Traumatic Spinal Cord Injuries

Spinal cord trauma constitutes one of the main causes of mortality and morbidity in young adults around the world, with an estimated 2 to 3 new cases for every 100,000 population. Road traffic accidents, falls from high heights, sports injuries, and violent actions are common causes of spinal cord injuries. There is no “gold standard” for the diagnosis of spinal cord traumatic injuries; however, the rational use of conventional radiologic test, computed tomography scan, and magnetic resonance imaging (MRI) will allow to identify almost all clinically relevant injuries. MRI is recommended according to surgeon’s criteria, who after evaluating the specific characteristics of the injury will determine its usefulness. Therapeutic strategies need to be directed to maintain airway, breathing and circulation, maintenance of mean arterial pressure prevention of hypotension, and assessment of other associated injuries. Intensive treatment must be focused on the prevention and management of ventilatory and cardiovascular abnormalities related to muscle weakness and loss of autonomic innervation.

Improved Functional Recovery in Rat Spinal Cord Injury Induced by a Drug Combination Administered with an Implantable Polymeric Delivery System

Spinal cord injury (SCI) is an incurable condition, in which a cascade of cellular and molecular events triggered by inflammation and excitotoxicity impairs endogenous regeneration, namely remyelination and axonal outgrowth. We designed a treatment solution based on an implantable biomaterial (electrospun poly (l-lactic acid) [PLLA]) loaded with ibuprofen and triiodothyronine (T3) to counteract inflammation, thus improving endogenous regeneration. In vivo efficacy was tested by implanting the drug-loaded PLLA in the rat model of T8 contusion SCI. We observed the expected recovery of locomotion beginning on day 7. In PLLA-implanted rats (i.e., controls), the recovery stabilized at 21 days post-lesion (DPL), after which no further improvement was observed. On the contrary, in PLLA + ibuprofen (Ibu) + T3 (PLLA-Ibu-T3) rats a further recovery and a significant treatment effect were observed, also confirmed by the gait analysis on 49 DPL. Glutamate release at 24 h and 8 DPL was reduced in PLLA-Ibu-T3- compared to PLLA-implanted rats, such as the estimated lesion volume at 60 DPL. The myelin- and 200-neurofilament-positive area fraction was higher in PLLA-Ibu-T3-implanted rats, where the percentage of astrocytes was significantly reduced. The implant of a PLLA electrospun scaffold loaded with Ibu and T3 significantly improves the endogenous regeneration, leading to an improvement of functional locomotion outcome in the SCI.

Emotional Interaction in Road Traffic Injury: A Qualitative Study On People With Spinal Cord Injury

The injury management in the acute phase of spinal cord injury starts at the accident scene and focuses on preventing and reducing secondary damages. The road traffic injured patients are mostly transferred by relatives, untrained laypeople, and the drivers of heavy vehicles. The current study explored the experience of people with spinal cord injury in the accident scene. This was a qualitative content analysis study using the semi-structured interviewing method with an interview guide for data collection. Purposive sampling method was performed within ten months until data saturation. We used the constant comparative approach recommended by Corbin and Strauss (2015). In total, 15 people with spinal cord injury and bystanders participated in this study. The central theme extracted in this study was "emotional interaction" that referred to the emotional reactions in managing road traffic victims. Two main categories of "emotional intervention" with "emotional atmosphere," "desperation," "rescue efforts," subcategories and "scene shock" with "unplanned intervention," "emotional behavior," "emotional decisions," and "emotional involvement," subcategories were classified. The emotional atmosphere of the scene and stress level of the victim and the relatives, and the insistence of the victim to escape from the harsh condition have caused those lacking medical knowledge and expertise to transfer the patient unsafely. This resulted in secondary damages, like aggravated spinal cord injury or even caused the spinal cord injury.

Current Topics in the Management of Acute Traumatic Spinal Cord Injury

Acute traumatic spinal cord injury (SCI) affects more than 250,000 people in the USA, with approximately 17,000 new cases each year. It continues to be one of the most significant causes of trauma-related morbidity and mortality. Despite the introduction of primary injury prevention education and vehicle safety devices, such as airbags and passive restraint systems, traumatic SCI continues to have a substantial impact on the healthcare system. Over the last three decades, there have been considerable advancements in the management of patients with traumatic SCI. The advent of spinal instrumentation has improved the surgical treatment of spinal fractures and the ability to manage SCI patients with spinal mechanical instability. There has been a concomitant improvement in the nonsurgical care of these patients with particular focus on care delivered in the pre-hospital, emergency room, and intensive care unit (ICU) settings. This article represents an overview of the critical aspects of contemporary traumatic SCI care and notes areas where further research inquiries are needed. We review the pre-hospital management of a patient with an acute SCI, including triage, immobilization, and transportation. Upon arrival to the definitive treatment facility, we review initial evaluation and management steps, including initial neurological assessment, radiographic assessment, cervical collar clearance protocols, and closed reduction of cervical fracture/dislocation injuries. Finally, we review ICU issues including airway, hemodynamic, and pharmacological management, as well as future directions of care.

A Review on the Etiology and Management of Pediatric Traumatic Spinal Cord Injuries

CONTEXT

Pediatric traumatic spinal cord injury (SCI) is an uncommon presentation in the emergency department. Severe injuries are associated with devastating outcomes and complications, resulting in high costs to both the society and the economic system.

EVIDENCE ACQUISITION

The data on pediatric traumatic spinal cord injuries has been narratively reviewed.

RESULTS

Pediatric SCI is a life-threatening emergency leading to serious outcomes and high mortality in children if not managed promptly. Pediatric SCI can impose many challenges to neurosurgeons and caregivers because of the lack of large studies with high evidence level and specific guidelines in terms of diagnosis, initial management and of in-hospital treatment options. Several novel potential treatment options for SCI have been developed and are currently under investigation. However, research studies into this field have been limited by the ethical and methodological challenges.

CONCLUSION

Future research is needed to investigate the safety and efficacy of the recent uprising neurodegenerative techniques in SCI population. Owing to the current limitations, there is a need to develop novel trial methodologies that can overcome the current methodological and ethical limitations.

Chondroitinase improves anatomical and functional outcomes after primate spinal cord injury

Inhibitory extracellular matrices form around mature neurons as perineuronal nets containing chondroitin sulfate proteoglycans that limit axonal sprouting after CNS injury. The enzyme chondroitinase (Chase) degrades inhibitory chondroitin sulfate proteoglycans and improves axonal sprouting and functional recovery after spinal cord injury in rodents. We evaluated the effects of Chase in rhesus monkeys that had undergone C7 spinal cord hemisection. Four weeks after hemisection, we administered multiple intraparenchymal Chase injections below the lesion, targeting spinal cord circuits that control hand function. Hand function improved significantly in Chase-treated monkeys relative to vehicle-injected controls. Moreover, Chase significantly increased corticospinal axon growth and the number of synapses formed by corticospinal terminals in gray matter caudal to the lesion. No detrimental effects were detected. This approach appears to merit clinical translation in spinal cord injury.

Zhenbao Pill reduces Treg cell proportion in acute spinal cord injury rats by regulating TUG1/miR-214/HSP27 axis

Background: Acute spinal cord injury (SCI) is one of the weakest pathologies that seriously affect the quality of life of patients. Objective: To study the mechanism of how Zhenbao Pill reduces Treg cell proportion and improves acute SCI. Methods: A rat SCI model was established. Flow cytometry analysis was performed to determine the Treg cell proportion. RNA immunoprecipitation (RIP) and RNA pull-down were applied in confirming taurine up-regulated gene 1 (TUG1) and miR-214 binding. Intrathecal injection of TUG1 siRNA was also conducted to determine the effect of TUG1 in vivoResults: Zhenbao Pill promoted the expression of TUG1 and heat shock protein 27 (HSP27) protein, and reduced the expression of miR-214 and forkhead box protein p3 (Foxp3) as well as Treg cell proportion in a concentration-dependent manner in SCI rats or in vitro cultured CD4+ T cells. Knockdown of TUG1 reversed the high protein expression of HSP27 and the inhibition of Treg cell proportion as well as Foxp3 protein induced by Zhenbao Pill, and miR-214 inhibitor canceled the TUG1 knockdown effect. Further, miR-214 mimic reversed the inhibition of Treg cell proportion and Foxp3 protein expression by Zhenbao Pill, which was abolished by the overexpression of HSP27. The mechanism was validated in animal experiments. Conclusion: Zhenbao Pill regulated TUG1/miR-214/HSP27 signaling pathway to reduce Treg cell proportion and thus relieve acute SCI.

Methotrexate remediates spinal cord injury in vivo and in vitro via suppression of endoplasmic reticulum stress-induced apoptosis

It has been suggested that endoplasmic reticulum stress (ERS) may induce apoptosis following spinal cord injury (SCI). Methotrexate (MTX) has been used as a long-term therapy regimen for rheumatoid arthritis. However, it is not clear whether MTX remediates SCI by inhibiting ERS. In the present study, to establish an in vitro ERS cell model, PC12 cells were pre-incubated with triglycerides (TG). MTT assays revealed that treatment with 1, 2.5, 5 and 10 µM TG decreased PC12 cell viability in a dose-dependent manner. Additionally, MTX treatment significantly reversed the TG-induced decrease in cell viability and increased apoptosis according to the flow cytometry assay (P<0.05). Notably, western blotting indicated that MTX significantly decreased levels of glucose-regulated protein (GRP)78, CCAAT-enhancer-binding protein homologous protein (CHOP) and caspase-12 expression (P<0.05), which were increased following treatment with TG. Furthermore, the in vivo role of MTX in a rat model of SCI was evaluated. The motor behavioral function of rats was improved following treatment with MTX according to Basso, Beattie and Bresnahan scoring (P<0.05). Terminal deoxynucleotidyl-transferase-mediated dUTP nick end staining indicated that there were no apoptotic cells present in sham rats. In the SCI model group, apoptotic cells were observed at day 7; however, the number of apoptotic cells was reduced following an additional 7 days of MTX administration. Furthermore, levels of ERS-associated proteins, including caspase-3, activating transcription factor 6, serine/threonine-protein kinase/endoribonuclease inositol-requiring enzyme 1 α, eukaryotic initiation factor 2 α and GRP78, were significantly increased following SCI; however, administration of MTX for 7 days significantly reversed this effect (P<0.05, P<0.01 and P<0.001). Therefore, MTX may improve SCI by suppressing ERS-induced apoptosis in vitro and in vivo.