Journal of neurotrauma
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Journal of neurotrauma · May 2012
Re-innervation of the bladder through end-to-side neurorrhaphy of autonomic nerve and somatic nerve in rats.
End-to-side neurorrhaphy is widely used in the peripheral nervous system for nerve repair; however, the application of this technique has been limited to somatic nerves. The feasibility of nerve regeneration through end-to-side neurorrhaphy between autonomic and somatic nerves with different characteristics in the peripheral nervous system is still undetermined. In this study, rats were divided into three groups for different treatments (n=10 per group). ⋯ Morphological examination and intravesical pressure measurement indicated prominent nerve regeneration and successful re-innervation of the bladder in the neurorrhaphy group, compared with the "no repair" group (p<0.05). No significant changes were observed in the histology of the donor nerve and the bilateral extensor digitorum longus muscles in the neurorrhaphy group. Nerve regeneration may be achievable for nerve repair through end-to-side neurorrhaphy between autonomic and somatic nerves without apparent impairment of donor somatic nerve.
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Journal of neurotrauma · May 2012
Nandrolone normalizes determinants of muscle mass and fiber type after spinal cord injury.
Spinal cord injury (SCI) results in atrophy of skeletal muscle and changes from slow oxidative to fast glycolytic fibers, which may reflect reduced levels of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), increased myostatin signaling, or both. In animals, testosterone reduces loss of muscle fiber cross-sectional area and activity of enzymes of energy metabolism. To identify the molecular mechanisms behind the benefits of androgens on paralyzed muscle, male rats were spinal cord transected and treated for 8 weeks with vehicle, testosterone at a physiological replacement dose, or testosterone plus nandrolone, an anabolic steroid. ⋯ Thus, the findings demonstrate that following SCI, signaling through activin receptors and Smad2/3 is increased, and that androgens suppress activation of this signaling pathway. The findings also indicate that androgens upregulate PGC-1α in paralyzed muscle and promote its nuclear localization, but that these effects are insufficient to fully activate transcription of PGC-1α target genes. Furthermore, the transcription of these genes is not tightly coupled with their translation.
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Journal of neurotrauma · May 2012
Transplantation of mesenchymal stem cells promotes an alternative pathway of macrophage activation and functional recovery after spinal cord injury.
Mesenchymal stem cells (MSC) derived from bone marrow can potentially reduce the acute inflammatory response in spinal cord injury (SCI) and thus promote functional recovery. However, the precise mechanisms through which transplanted MSC attenuate inflammation after SCI are still unclear. The present study was designed to investigate the effects of MSC transplantation with a special focus on their effect on macrophage activation after SCI. ⋯ This was associated simultaneously with increased numbers of alternatively activated macrophages (M2 phenotype: arginase-1- or CD206-positive), and decreased numbers of classically activated macrophages (M1 phenotype: iNOS- or CD16/32-positive). These changes were associated with functional locomotion recovery in the MSC-transplanted group, which correlated with preserved axons, less scar tissue formation, and increased myelin sparing. Our results suggested that acute transplantation of MSC after SCI modified the inflammatory environment by shifting the macrophage phenotype from M1 to M2, and that this may reduce the effects of the inhibitory scar tissue in the subacute/chronic phase after injury to provide a permissive environment for axonal extension and functional recovery.
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Journal of neurotrauma · May 2012
The delayed post-injury administration of soluble fas receptor attenuates post-traumatic neural degeneration and enhances functional recovery after traumatic cervical spinal cord injury.
Spinal cord injury (SCI) is a devastating condition that currently lacks clinically-relevant and effective neuroprotective therapeutic options. Optimal therapeutic agents for clinical translation should show efficacy in a cervical compression/contusion model using a clinically-relevant post-injury therapeutic time window. To date, few compounds have met that rigorous standard. ⋯ In animals treated with sFasR delayed 8 h post-injury, significant behavioral effects were observed, coinciding with enhanced cell survival, peri-lesional tissue sparing, and enhanced integrity of descending fiber tracts compared to control treatments. Animals treated with sFasR delayed by 24 h showed more modest improvements in behavioral recovery, and had consistent improvements in cell survival and tissue preservation. This work has shown for the first time that the Fas-mediated apoptotic pathway can be therapeutically targeted in a clinically-relevant time window post-SCI.
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Journal of neurotrauma · May 2012
ReviewAn overview of published research about the acute care and rehabilitation of traumatic brain injured and spinal cord injured patients.
Knowledge of the breadth, nature, and volume of traumatic brain injury (TBI) and spinal cord injury (SCI) research can aid in research planning. This study aimed to provide an overview of existing TBI and SCI research to inform identification of knowledge translation (KT), systematic review (SR), and primary research opportunities. Topics and relevant articles from three large neurotrauma evidence resources were synthesized: the Global Evidence Mapping (GEM) Initiative (129 topics and 1644 articles), the Acquired Brain Injury Evidence-Based Review (ERABI; 152 topics and 732 articles), and the Spinal Cord Injury Rehabilitation Evidence (SCIRE) Project (297 topics and 1650 articles). ⋯ Topics for which primary research may be needed included pharmacological therapies for neurological recovery post-TBI, and management of sleep-disordered breathing post-SCI. There was a larger volume of non-intervention (epidemiological) studies in SCI than in TBI. This comprehensive overview of TBI and SCI research can aid funding agencies, researchers, clinicians, and other stakeholders in prioritizing and planning TBI and SCI research.