Magnesium administration after experimental traumatic brain injury improves decision-making skills.

After sustaining a traumatic brain injury (TBI), a person's ability to make daily decisions can be affected. Simple tasks such as, deciding what to wear are no longer effortless choices, but are instead difficult decisions. This study explored the use of a discrimination task with a magnesium treatment in order to examine how decision-making skills are affected after TBI and if the treatment helped to attenuate cognitive and motor impairments. Thirty-one male rats were separated into MAG/TBI, VEH/TBI, or VEH/Sham groups. Pre-TBI, rats were trained to dig in the sand for a reinforcer. After establishment of consistent digging behavior rats received a bilateral frontal cortex injury. Rats received either an i.p. injection of 2 mmol/kg magnesium chloride or control at 4, 24, 72 h post-surgery. Dig task testing began 7 days post-injury, lasting for 4 weeks. The discriminations included two scent pairings; basil (baited) versus coffee then the reversal and then cocoa (baited) versus cumin then the reversal. The results indicated that the magnesium treatment was successful at attenuating cognitive and motor deficits after TBI. The results also indicated that the dig task is a sufficient operant conditioning task in the assessment of frontal functioning after TBI.

Environmental enrichment aides in functional recovery following unilateral controlled cortical impact of the forelimb sensorimotor area however intranasal administration of nerve growth factor does not.

PURPOSE: An injury to the forelimb sensorimotor cortex results in the impairment of motor function in animals. Recent research has suggested that intranasal administration of nerve growth factor (NGF), a protein naturally found in the brain, and placement into enriched environments (EE) improves motor and cognitive function after traumatic brain injury (TBI). The purpose of this study was to determine whether NGF, EE, or the combination of both was beneficial in the recovery of motor function following TBI. RESULTS: Uninjured animals had fewer foot faults than injured animals, displaying a lesion effect. Injured animals housed in EE were shown to have fewer foot faults whether or not they received NGF. Injured animals also displayed an increased reliance on the non-impaired limb further validating a lesion effect. CONCLUSION: EE is an effective treatment on the recovery of motor function after a TBI. Intranasal administration of NGF was found to not be an effective treatment for functional motor recovery after a TBI.

Combining enriched environment and induced pluripotent stem cell therapy results in improved cognitive and motor function following traumatic brain injury.

PURPOSE: Despite advances towards potential clinically viable therapies there has been only limited success in improving functional recovery following traumatic brain injury (TBI). In rats, exposure to an enriched environment (EE) improves learning and fosters motor skill development. Induced pluripotent stem cells (iPSC) have been shown to survive transplantation and influence the recovery process. The current study evaluated EE and iPSC as a polytherapy for remediating cognitive deficits following medial frontal cortex (mFC) controlled cortical impact (CCI) injury. METHODS: Sixty adult male rats received a midline mFC CCI or sham injury and were randomly placed in either EE or standard environment (SE). Seven days post-injury rats received bilateral transplantation of iPSCs or media. Behavioral measures were conducted throughout the remainder of the study. Following behavioral analysis, brains were extracted and prepared for histological analysis. RESULTS: Open-field data revealed that combined therapy resulted in typical Sham/EE activity rearing patterns by the conclusion of the study. On the Vermicelli Handling task, rats with EE/iPSC polytherapy performed better than media-treated rats. Furthermore, rats treated with polytherapy performed equivalently to Sham/EE rats on the Morris water maze. Proficiency on the Rotarod was consistently better in EE when compared to SE counterparts. Confocal microscopy confirmed that iPSCs survived and migrated away from the transplantation site. CONCLUSIONS: Overall, EE or iPSC therapy improved cognition and motor performance, however, full cognitive restoration was seen only with the EE/iPSC treatment. These data suggest that EE/iPSC therapy should be explored as a potential, clinically relevant, treatment for TBI.