Journal of neurotrauma
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Journal of neurotrauma · Dec 2018
Longitudinal Magnetic Resonance Imaging Analysis and Histological Characterization after Spinal Cord Injury in Two Mouse Strains with Different Functional Recovery: Gliosis as a Key Factor.
Spinal cord injuries (SCI) are disastrous neuropathologies causing permanent disabilities. The availability of different strains of mice is valuable for studying the pathophysiological mechanisms involved in SCI. However, strain differences have a profound effect on spontaneous functional recovery after SCI. ⋯ All three modalities revealed no difference in lesion extension and volume between the two strains of mice. Importantly, histopathological analysis identified decreased gliosis and increased serotonergic axons in CX3CR1+/eGFP compared with Aldh1l1-EGFP mice following SCI. These results thus suggest that the strain-dependent improved functional recovery after SCI may be linked with reduced gliosis and increased serotonergic innervation.
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Journal of neurotrauma · Dec 2018
Systemic and Cerebral Hemodynamic Contribution to Cognitive Performance in Spinal Cord Injury.
Cognitive deficits are prevalent in the spinal cord injury (SCI) population, and consensus suggests that concomitant traumatic brain injury or comorbid conditions are primarily responsible for these deficits. However, mounting evidence supports the possibility that systemic and cerebral hemodynamic dysfunction may contribute to the cognitive deficits reported in persons with SCI. We sought to determine the contribution of changes in blood pressure (BP) and changes in cerebral blood flow velocity (CBFv) to test performance on the Symbol Digit Modalities Test (SDMT) in persons with SCI compared with matched non-SCI controls. ⋯ Further, change in SBP accounted for a significant amount of variance in change in DFV in the total study sample (r2 = 0.090; p = 0.002). These results support previous findings of cognitive deficits in persons with SCI and indicate that inadequate systemic and cerebral hemodynamic responses to testing contribute to test performance. Therefore, clinical treatment of cognitive dysfunction in the SCI population should consider focusing on increasing systemic BP to improve CBFv, particularly in individuals with lesions above T1.
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Journal of neurotrauma · Dec 2018
Transplantation of Neural Progenitors and V2a Interneurons after Spinal Cord Injury.
There is growing interest in the use of neural precursor cells to treat spinal cord injury (SCI). Despite extensive pre-clinical research, it remains unclear as to which donor neuron phenotypes are available for transplantation, whether the same populations exist across different sources of donor tissue (e.g., developing tissue vs. cultured cells), and whether donor cells retain their phenotype once transplanted into the hostile internal milieu of the injured adult spinal cord. In addition, while functional improvements have been reported after neural precursor transplantation post-SCI, the extent of recovery is limited and variable. ⋯ Functional diaphragm electromyography indicated recovery 1 month following treatment in transplant recipients. Animals that received donor cells enriched with V2a INs showed significantly greater functional improvement than animals that received NPCs alone. The results from this study offer insight into the neuronal phenotypes that might be effective for (re)establishing neuronal circuits in the injured adult central nervous system.
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Journal of neurotrauma · Dec 2018
Enhanced Voluntary Exercise Improves Functional Recovery following Spinal Cord Injury by Impacting the Local Neuroglial Injury Response and Supporting the Rewiring of Supraspinal Circuits.
Recent reports suggest that rehabilitation measures that increase physical activity of patients can improve functional outcome after incomplete spinal cord injuries (iSCI). To investigate the structural basis of exercise-induced recovery, we examined local and remote consequences of voluntary wheel training in spinal cord injured female mice. In particular, we explored how enhanced voluntary exercise influences the neuronal and glial response at the lesion site as well as the rewiring of supraspinal tracts after iSCI. ⋯ Enhanced voluntary exercise improved their overall and skilled motor function after injury. In addition, exercising mice started to recover earlier and reached better sustained performance levels. These improvements in motor performance are accompanied by early changes of axonal and glial response at the lesion site and persistent enhancements of the rewiring of supraspinal connections that resulted in a strengthening of both indirect and direct inputs to lumbar motoneurons.
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Journal of neurotrauma · Dec 2018
Clinical TrialVisibility Graph Analysis of Intraspinal Pressure Signal Predicts Functional Outcome in Spinal Cord Injured Patients.
To guide management of patients with acute spinal cord injuries, we developed intraspinal pressure monitoring from the injury site. Here, we examine the complex fluctuations in the intraspinal pressure signal using network theory. We analyzed 7097 h of intraspinal pressure data from 58 patients with severe cord injuries. ⋯ In a multivariate logistic regression model, age, neurological status on admission, and average node eccentricity were independent predictors of neurological improvement. We conclude that analysis of intraspinal pressure fluctuations after spinal cord injury as graphs, rather than as time series, captures clinically important information. Our novel technique may be applied to other signals recorded from injured central nervous system (CNS); for example, intracranial pressure, tissue metabolite, and oxygen levels.