Abstract:

BACKGROUND: In recent years, mild hypothermia (33-35 ℃) in the treatment of brain and spinal cord injury obtains more and more attention. Many clinical studies have shown that mild hypothermia can reduce secondary brain and spinal cord injury, and play a precise protective role in central nervous injury in rats.
OBJECTIVE: To determine whether mild hypothermia can enhance curative effects of stereotactic transplantation of bone marrow mesenchymal stem cells (BMSCs) on traumatic brain injury (TBI) in rats.
METHODS: BMSCs were cultured by the suspension culture in vitro. The models of severe TBI were made in rats by given 253.31-303.98 kPa power of hydraulic impact. BMSCs were stereotactically transplantated into the brain in the rats with TBI 24 hours after TBI, and the rats were divided into three groups, group A: TBI; group B: BMSCs transplantation group; group C: BMSCs transplantation+hypothermia group. After 3 days, AQP4 expression was determined by Western Blot, the water contents in the brain tissues were measured as wet-to-dry weight ratio. The neurological defect scores were determined after 24 hours, 3 days and 1, 2 weeks after TBI. The immunohistochemistry and pathology were checked after 2 weeks.
RESULTS AND CONCLUSION: Three days after brain injury, compared with A group and B group, the expression of AQP4 detected by Western Blot and cerebral edema detected by wet-to-dry weight ratio were decreased (P  < 0.05). The neurological defect scores were significantly lower in group C than those in groups A and B at 1 and 2 weeks after TBI (P < 0.05). The number of neurons in group C was higher than that in groups A and B (P < 0.01). These findings show that stereotactic transplantation of BMSCs combined with mild hypothermia can significantly improve the neurological function in the rats with TBI.