Antioxidative therapy in contusion spinal cord injury.

INTRODUCTION: Some studies have made use of the antioxidative capabilities of high doses of vitamins C and E with the aim of neutralizing the noxious effects of free radicals following spinal cord lesion. OBJECTIVES: To evaluate the effects of vitamins C and E, separately and together, on the functional performance of rats that were subjected to standardized spinal cord contusion. MATERIALS AND METHODS: Forty male Wistar rats were used, divided into four groups of 10 animals each. Group 3 received vitamin C 100 mg kg(-1) day(-1) intraperitoneally; Group 2 received vitamin E 100 mg kg(-1) day(-1) orally; Group 1 received vitamins C and E, at the same dosages; and Group 4 was the control. The vitamin therapy was administered for 1 month and then the animals were killed. A direct contusional injury was caused and functional evaluation was performed using the Basso, Beattie and Bresnahan rating scale. The rats were evaluated on the second postoperative day and weekly thereafter, until the end of the experiment. RESULTS: The results were evaluated by means of the one-tailed, non-paired and non-parametric Mann-Whitney test, comparing the groups two by two. No significant difference in functional performance was observed between the groups. CONCLUSION: The use of vitamins C and E in these rats did not improve their neurological performance. However, histopathological examination showed that the inflammatory response was less intense following administration of the combination of vitamins C and E.

Contuse lesion of the rat spinal cord of moderate intensity leads to a higher time-dependent secondary neurodegeneration than severe one. An open-window for experimental neuroprotective interventions.

Secondary neurodegeneration takes place in the surrounding tissue of spinal cord trauma and modifies substantially the prognosis, considering the small diameter of its transversal axis. We analyzed neuronal and glial responses in rat spinal cord after different degree of contusion promoted by the NYU Impactor. Rats were submitted to vertebrae laminectomy and received moderate or severe contusions. Control animals were sham operated. After 7 and 30 days post surgery, stereological analysis of Nissl staining cellular profiles showed a time progression of the lesion volume after moderate injury, but not after severe injury. The number of neurons was not altered cranial to injury. However, same degree of diminution was seen in the caudal cord 30 days after both severe and moderate injuries. Microdensitometric image analysis demonstrated a microglial reaction in the white matter 30 days after a moderate contusion and showed a widespread astroglial reaction in the white and gray matters 7 days after both severities. Astroglial activation lasted close to lesion and in areas related to Wallerian degeneration. Data showed a more protracted secondary degeneration in rat spinal cord after mild contusion, which offered an opportunity for neuroprotective approaches. Temporal and regional glial responses corroborated to diverse glial cell function in lesioned spinal cord.