Temporally Specified Genetic Ablation of Neurogenesis Impairs Cognitive Recovery after Traumatic Brain Injury

Significant spontaneous recovery occurs after essentially all forms of serious brain injury, but the mechanisms underlying this recovery are not clear. Given that many forms of brain injury such as traumatic brain injury induce hippocampal neurogenesis, the authors investigated whether these newly generated neurons might play a role in cognitive recovery. By modeling traumatic brain injury in transgenic mice, they determined that injury-induced newly generated neurons persisted over time and elaborated extensive dendritic trees that stably incorporated themselves throughout all neuronal layers of the dentate gyrus. When they specifically eliminated injury-induced neurogenesis (using ganciclovir in a nestin-HSV-TK transgenic model), they found that only injured animals with neurogenesis ablated at the time of injury lost the ability to learn spatial memory tasks. The data demonstrate a functional role for adult neurogenesis after brain injury and suggest testable therapeutic options that might enhance recovery.
Blaiss CA et al., Temporally Specified Genetic Ablation of Neurogenesis Impairs Cognitive Recovery after Traumatic Brain Injury. J. Neuroscience 31 (13): 4906-4916 (2011).
http://www.jneurosci.org/content/31/13/4906.abstract?etoc