Journal of neurotrauma
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Journal of neurotrauma · May 2022
Rostral-caudal effect of cervical magnetic stimulation on the diaphragm motor evoked potential following cervical spinal cord contusion in the rat.
The present study was designed to investigate the rostral-caudal effect of spinal magnetic stimulation on diaphragmatic motor-evoked potentials after cervical spinal cord injury. The diaphragm electromyogram was recorded in rats that received a laminectomy or a left midcervical contusion at the acute (1 day), subchronic (2 weeks), or chronic (8 weeks) injury stages. The center of a figure-eight coil was placed at 30 mm lateral to bregma on the left side, and the effect of magnetic stimulation was evaluated by stimulating the rostral, middle, and caudal cervical regions in spontaneously breathing rats. ⋯ In addition, in contused animals but not uninjured animals, diaphragmatic motor-evoked potential amplitudes were greater at the chronic stage than during earlier injury stages. These results demonstrated that cervical magnetic stimulation can excite the residual phrenic motor circuit to activate the diaphragm in the presence of a significant lesion in the cervical spinal cord. These findings indicate that this non-invasive approach is effective for modulating diaphragmatic excitability after cervical spinal cord injury.
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Journal of neurotrauma · May 2022
Suppression of TRPM7 by carvacrol protects against injured spinal cord by inhibiting blood-spinal cord barrier disruption.
When the blood-spinal cord barrier (BSCB) is disrupted after a spinal cord injury (SCI), several pathophysiological cascades occur, including inflammation and apoptotic cell death of neurons and oligodendrocytes, resulting in permanent neurological deficits. Transient receptor potential melastatin 7 (TRPM7) is involved in the pathological processes in many neuronal diseases, including traumatic brain injury, amyotrophic lateral sclerosis, parkinsonism dementia, and Alzheimer's disease. Further, carvacrol (CAR), a TRPM7 inhibitor, is known to protect against SCI by reducing oxidative stress and inhibiting the endothelial nitric oxide synthase pathway. ⋯ Additionally, CAR treatment suppressed BSCB disruption by inhibiting the loss of tight junction (TJ) proteins and preserved TJ integrity. CAR also reduced apoptotic cell death and improved functional recovery after SCI by preventing BSCB disruption caused by blood infiltration and inflammatory responses. Based on these findings, we propose that blocking the TRPM7 channel can inhibit the destruction of the BSCB and it is a potential target in therapeutic drug development for use in SCI.
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Journal of neurotrauma · Apr 2022
Combined Inhibition of Fyn and c-Src Protects Hippocampal Neurons and Improves Spatial Memory via ROCK after Traumatic Brain Injury.
Our previous studies demonstrated that traumatic brain injury (TBI) and ventricular administration of thrombin caused hippocampal neuron loss and cognitive dysfunction via activation of Src family kinases (SFKs). Based on SFK localization in brain, we hypothesized SFK subtypes Fyn and c-Src, as well as SFK downstream molecule Rho-associated protein kinase (ROCK), contribute to cell death and cognitive dysfunction after TBI. We administered nanoparticle wrapped small interfering RNA (siRNA)-Fyn and siRNA-c-Src, or ROCK inhibitor Y-27632 to adult rats subjected to moderate lateral fluid percussion (LFP)-induced TBI. ⋯ The combination of siRNA-Fyn and siRNA-c-Src, but neither alone, prevented hippocampal neuron loss and spatial memory deficits after TBI. The ROCK inhibitor Y-27632 also prevented hippocampal neuronal loss and spatial memory deficits after TBI. The data suggest that the combined actions of three kinases (Fyn, c-Src, ROCK) mediate hippocampal neuronal cell death and spatial memory deficits produced by LFP-TBI, and that inhibiting this pathway prevents the TBI-induced cell death and memory deficits.
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Journal of neurotrauma · Apr 2022
Review Meta AnalysisMild Traumatic Brain Injury in Elderly Patients Receiving Direct Oral Anticoagulants: A Systematic Review and Meta-Analysis.
The aim of this work was to conduct a systematic review and meta-analysis of studies reporting on the risk of traumatic intracerebral hemorrhage (tICH), the course of tICH, and its treatment and mortality rates in elderly mild traumatic brain injury (mTBI) patients using direct oral anticoagulants (DOACs). We consulted PubMed and Embase for relevant cohort and case-control studies with a control group. Two authors independently selected studies, assessed methodological quality, and extracted outcome data. ⋯ There was no significant difference in neurosurgical intervention rate between patients who used DOACs versus patients who used APT (OR, 0.58; 95% CI, 0.15-2.21; I2 = 41%) or no antithrombotic therapy (OR, 0.76; 95% CI, 0.20-2.86; I2 = 23%). ICH progression, risk of delayed ICH, and TBI-related in-hospital mortality were comparable among treatment groups. The present study indicates that elderly patients using DOACs have a lower risk of adverse outcome compared to patients using VKAs and a similar risk compared to patients using APT after mTBI.