Management of chronic spinal cord dysfunction

Prognostic Value of Malondialdehyde (MDA) in the Temporal Progression of Chronic Spinal Cord Injury

Background: Oxidative stress is a major signature of spinal cord injury (SCI). The altered levels of various oxidative stress markers have been demonstrated in acute and chronic SCI. However, the variation of these markers in patients with chronic SCI depending on the time since the initial injury has not been explored yet. Objective: Our aim was to measure plasma levels of malondialdehyde (MDA), a marker of lipid peroxidation in patients with SCI stratified in different periods of suffering the injury (0–5 years, 5–10 years, and more than 10 years). Patients and methods: This cross-sectional study enrolled patients with SCI (N = 105) from different periods of the lesion and healthy control (HC) subjects (N = 38): short period (SCI SP, N = 31, time of evolution less than 5 years); early chronic (SCI ECP, N = 32, time of evolution 5–15 years); and late chronic (SCI LCP, N = 42, time of evolution more than 15 years). The plasma levels of MDA were measured using a commercially available colorimetric assay. Results: Patients with SCI had significantly higher plasma levels of MDA than HC subjects. Receiver operating characteristic (ROC) curve analysis for plasma MDA levels in patients with SCI demonstrated areas under the curve (AUC) of 1 (HC vs. SCI-SP); 0.998 (HC vs. SCI-ECP); and 0.964 (HC vs. SCI-LCP). Additionally, three ROC curves were used to compare the different concentrations of MDA between the subgroups of patients with SCI, and the resulting AUCs were: 0.896 (SCI-SP vs. SCI-ECP); 0.840 (SCI-ECP vs. SCI-LCP); and 0.979 (SCI-SP vs. SCI-LCP). Conclusion: Plasma concentration of MDA can be considered as an oxidative stress biomarker to assess the prognosis of SCI in chronic stages.

Neural Stem Cells Overexpressing Arginine Decarboxylase Improve Functional Recovery from Spinal Cord Injury in a Mouse Model

Current therapeutic strategies for spinal cord injury (SCI) cannot fully facilitate neural regeneration or improve function. Arginine decarboxylase (ADC) synthesizes agmatine, an endogenous primary amine with neuroprotective effects. Transfection of human ADC (hADC) gene exerts protective effects after injury in murine brain-derived neural precursor cells (mNPCs). Following from these findings, we investigated the effects of hADC-mNPC transplantation in SCI model mice. Mice with experimentally damaged spinal cords were divided into three groups, separately transplanted with fluorescently labeled (1) control mNPCs, (2) retroviral vector (pLXSN)-infected mNPCs (pLXSN-mNPCs), and (3) hADC-mNPCs. Behavioral comparisons between groups were conducted weekly up to 6 weeks after SCI, and urine volume was measured up to 2 weeks after SCI. A subset of animals was euthanized each week after cell transplantation for molecular and histological analyses. The transplantation groups experienced significantly improved behavioral function, with the best recovery occurring in hADC-mNPC mice. Transplanting hADC-mNPCs improved neurological outcomes, induced oligodendrocyte differentiation and remyelination, increased neural lineage differentiation, and decreased glial scar formation. Moreover, locomotor and bladder function were both rehabilitated. These beneficial effects are likely related to differential BMP-2/4/7 expression in neuronal cells, providing an empirical basis for gene therapy as a curative SCI treatment option.

Analysis of gene expression profiles in two spinal cord injury models

Objectives

To analyze the changes of gene expression at different timepoints after spinal cord injury (SCI) with tenth segment thoracic injury.

Methods

Two SCI models, the complete paraplegia (H) and Allen’s strike (D) methods were applied to induce SCI in rats, and transcriptome sequencing was performed 1, 3, 7, 14, 56, and 70 days after SCI, respectively. Principal component analysis, differentially expressed gene analysis, and hierarchical clustering analysis were applied to analyze the differentially expressed genes (DEGs). Gene Ontology GO enrichment analysis, Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and Gene Set Enrichment Analysis revealed the pathway of gene enrichment.

Results

There were 1,907, 3,120, 3,728, 978, 2,319, and 3,798 DEGs in the complete paraplegia group and 2,380, 878, 1,543, 6,040, 1,945, and 3,850 DEGs in the Allen’s strike method group and after SCI at 1, 3, 7, 14, 56, and 70 days, respectively. The transcriptome contours of D1, H1, D3, and H14 were clustered with C; the H56, D56, H70, and D70 transcriptome contours were similar and clustered together. H3, D7, and H7 were clustered together, and D14 was clustered separately. The transcriptome differences of the two SCI models were mainly concentrated during the first 2 weeks after SCI. The DEGs after SCI in the complete paraplegia group were more concentrated. Most of the early transcriptional regulation stabilized within 2 weeks after injury.

Conclusions

There were DEGs between the two SCI models. Through the gene changes and pathway enrichment of the entire time period after SCI, the molecular mechanism of SCI repair was revealed in depth, which provided a reference for SCI treatment in the future.

A Review of Low-Level Laser Therapy for Spinal Cord Injury: Challenges And Safety

Introduction: Damage to the spinal cord is a central nervous system disorder that results in direct damage to neural cells (axons, cell bodies) and glia, followed by autonomic, motor and sensory impairments. Inflammatory response after this injury can contribute to secondary tissue damage that leads to further behavioral and functional disorders. Inflammation is a complex process, which occurs after an injury. If this progressive process is not well controlled can lead to additional damage to the spinal cord which is preventing neural improvement and regeneration and, which ultimately will not provide good clinical consequences. Inflammation in the injured spinal cord is a physiological response that causes the death of glial and neuronal cells. The reduction of the initial inflammatory process after damage to the spinal cord is one of the important therapeutic strategies. It has been proposed that low-level laser (LLL) therapy, as a noninvasive manner, can modulate inflammatory processes, which leads to a significant improvement in neurological symptoms after spinal cord injury (SCI). Methods: A comprehensive review was performed on SCI, the etiologies, and treatment methods using the keywords spinal cord injury, low-level laser, and inflammation in valid medical databases such as Google Scholar, PubMed, and Elsevier (76 articles). Among the collected papers, articles that were most relevant to the purposes of the study were selected and studied. Results: LLL therapy was able to reduce inflammation and also attenuate neuronal damage after spinal cord damage. Conclusion: The present study illustrates that LLL therapy has positive effects on improving functional recovery and regulating the inflammatory function in the SCI.

Family-centered empowerment process in individuals with spinal cord injury living in Iran: a grounded theory study

STUDY DESIGN

This was a qualitative study using grounded theory method.

OBJECTIVES

To explain the process of family-centered empowerment in a population of individuals with SCI living in Iran.

SETTING

Brain and SCI Research Center, Social Welfare Center, and SCI Association of Tehran; Iran.

METHODS

Participants were 19 persons with traumatic SCI, 13 family member caregivers, and 11 health care providers selected through purposeful sampling. Data were collected using face-to-face, semi-structured interviews, which were continued until data saturation. The interview data were methodically collected and analyzed using Strauss and Corbin's (1998) recommended method for grounded theory. Constant comparative analysis was simultaneously conducted through reviews of the interview statements, observations of behavior, interviewer field notes, and interviewer memos. The analysis was managed in MAXQDA software version 10.

RESULTS

The process of family-centered empowerment following SCI included five categories: (1) disruption in the existential integrity of the individual; (2) constructive life recovery; (3) inhibitors of family-centered empowerment; (4) facilitators of family-centered empowerment, and (5) back on track. Constructive life recovery was selected as the core variable using the grounded theory method. This core variable identified the strategies most frequently used by the participants to cope with the challenges of SCI-related impairment, disability, and overall life management.

CONCLUSIONS

Family-centered empowerment process in individuals with SCI living in Iran emerged from the data. The model includes early disruptions in the bio-psycho-social and vocational lives of individuals with SCI and their families, strategies for recovery post injury, inhibitors and facilitators of family-centered empowerment, the gradual return to work and daily activities, and the expected social roles for individuals with SCI.

Experimental Models of Spinal Cord Injury in Laboratory Rats

Pathologies associated with spinal cord injury are some of the leading diseases in the world. The search for new therapeutic agents and 3D biodegradable materials for the recovery of spinal cord functions is a topical issue. In this review, we have summarized the literature data on the most common experimental models of spinal cord injury in laboratory rats and analyzed the experience of using 3D biodegradable materials (scaffolds) in experimental studies of spinal trauma. The advantages and disadvantages of the described models are systematically analyzed in this review.

Epidemiology of Isolated Versus Nonisolated Mild Traumatic Brain Injury Treated in Emergency Departments in the United States, 2006-2012: Sociodemographic Characteristics

OBJECTIVES

To describe the frequencies and rates of mild traumatic brain injury (mTBI) emergency department (ED) visits, analyze the trend across the years, and compare sociodemographic characteristics of visits by mTBI type (ie, mTBI as the only injury, or present along with other injuries).

DESIGN

Population-based descriptive study using data from the Nationwide Emergency Department Sample (2006-2012).

METHODS

Joinpoint regression was used to calculate the average annual percent changes of mTBI incidence rates. Characteristics between isolated and nonisolated visits were compared, and the odds ratios were reported.

RESULTS

The rate per 100 000 population of mTBI ED visits in the United States increased significantly from 569.4 (in 2006) to 807.9 (in 2012). The highest rates were observed in 0- to 4-year-olds, followed by male 15- to 24-year-olds and females 65 years and older; the lowest rates were among 45- to 64-year-olds. The majority (70%) of all visits were nonisolated and occurred more frequently in residents of metropolitan areas. Falls were the leading external cause. Most visits were privately insured or covered by Medicare/Medicaid, and the injury occurred on weekdays in predominantly metropolitan hospitals in the South region.

CONCLUSIONS

The burden of mTBI in US EDs is high. Most mTBI ED visits present with other injuries. Awareness of sociodemographic factors associated with nonisolated mTBI may help improve diagnosis in US EDs. This information has implications for resource planning and mTBI screening in EDs.

Rat models of spinal cord injury: from pathology to potential therapies

A long-standing goal of spinal cord injury research is to develop effective spinal cord repair strategies for the clinic. Rat models of spinal cord injury provide an important mammalian model in which to evaluate treatment strategies and to understand the pathological basis of spinal cord injuries. These models have facilitated the development of robust tests for assessing the recovery of locomotor and sensory functions. Rat models have also allowed us to understand how neuronal circuitry changes following spinal cord injury and how recovery could be promoted by enhancing spontaneous regenerative mechanisms and by counteracting intrinsic inhibitory factors. Rat studies have also revealed possible routes to rescuing circuitry and cells in the acute stage of injury. Spatiotemporal and functional studies in these models highlight the therapeutic potential of manipulating inflammation, scarring and myelination. In addition, potential replacement therapies for spinal cord injury, including grafts and bridges, stem primarily from rat studies. Here, we discuss advantages and disadvantages of rat experimental spinal cord injury models and summarize knowledge gained from these models. We also discuss how an emerging understanding of different forms of injury, their pathology and degree of recovery has inspired numerous treatment strategies, some of which have led to clinical trials.

Summary: In this Review, we discuss the advantages and disadvantages of the rat for studies of experimental spinal cord injury and summarize the knowledge gained from such studies.