Establishment and Evaluation of a Novel High-Efficiency Model of Graded Traumatic Brain Injury in Mice

BACKGROUND: Although previous studies have made significant contributions to establishing animal traumatic brain injury (TBI) models for simulation of human TBI, the accuracy, controllability, and modeling efficiency of animal TBI models need to be further improved. This study established a novel high-efficiency graded mouse TBI model induced by shock wave. METHODS: A total of 125 mice were randomly divided into sham, 0.7 mm, 0.6 mm, and 0.5 mm groups according to the depth of the cross groove of the aluminum sheets. The stability and repeatability of apparatus were evaluated, and the integrity of the blood-brain barrier, cerebral edema, neuropathologic immunohistochemistry, apoptosis-related protein, and behavioral tests of neurologic function were used to validate this new model. RESULTS: The results showed that 4 mice were injured simultaneously in 1 experiment. They received the same intensity of shock waves. Moreover, the mortality rates caused by 3 different aluminum sheets were consistent with the mortality rates of mild TBI, moderate TBI, and severe TBI. Compared with the sham group, mice in different injured groups significantly increased brain water content, blood-brain barrier permeability, and neuronal apoptosis. And the mice in all injured groups showed poor motor ability, balancing, spatial learning, and memory abilities. CONCLUSIONS: The novel TBI apparatus has advantages in its small size, simple operation, high repeatability, high efficiency, and graded severity. Our TBI apparatus provides a novel tool to investigate the neuropathologic changes and underlying mechanisms of TBI with various levels of severities.