Following traumatic brain injury (TBI), patients often develop significant disability in cognition, communication, and behavioral or emotional stability. Problems with memory commonly occur following TBI and underlie some of the morbidity accompanying each of these affected areas. In addition, there is some spontaneous recovery after brain injury that occurs largely by unknown remodeling processes. It has been known for some time that TBI elicits increased generation of new neurons in the hippocampus;the significance of this, however, has not been clear. We have recently demonstrated that injury-induced neurogenesis underlies at least some of the spontaneous recovery associated with TBI. As such, the promotion of hippocampal neurogenesis represents an important therapeutic target for developing new treatments for victims of TBI. If injury-induced activation of hippocampal progenitors is useful at improving functional outcome, one reasonable approach to enhancing recovery would be to increase the proliferation of early progenitors. We have recently developed, characterized, and validated a novel transgenic mouse that allows for ganciclovir-induced ablation of actively dividing early neural progenitors, enabling us to precisely attribute any positive effects of pro-neurogenic strategies to their effects on neurogenesis. The overall goal of this project is to determine whether enhancing neurogenesis improves outcome following TBI.
In Specific Aim 1, we will enhance hippocampal neurogenesis using pharmacologic means. We will test an FDA-approved medication commonly used to treat Alzheimer disease and determine whether it specifically enhances neurogenesis in the hippocampus following injury.
For Specific Aim 2, we will utilize temporally regulated and progenitor-specific genetic deletion of the tumor suppressor gene PTEN that also specifically increases hippocampal neurons. For both of these, we will study the effects of increasing neurogenesis following controlled cortical impact (CCI) injury to determine whether enhancing neurogenesis improves recovery after TBI.

Public Health Relevance

Following traumatic brain injury (TBI), patients often develop persistent disabilities, and specific problems with memory underlie much of the long-term adverse outcomes associated with serious brain injury. We have recently demonstrated that the some of the spontaneous recovery that occurs after TBI is due to generation of new neurons within the hippocampus, the part of the brain that mediates memory formation. The purpose of this proposal is to determine whether enhancing this process can further improve recovery following TBI and thereby open new avenues towards treatment in individuals suffering from these kinds of injuries.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21NS083077-01A1
Application #
8596011
Study Section
Brain Injury and Neurovascular Pathologies Study Section (BINP)
Program Officer
Hicks, Ramona R
Project Start
2013-06-01
Project End
2015-05-30
Budget Start
2013-06-01
Budget End
2014-05-31
Support Year
1
Fiscal Year
2013
Total Cost
$200,000
Indirect Cost
$75,000
Name
Columbia University (N.Y.)
Department
Pediatrics
Type
Schools of Medicine
DUNS #
621889815
City
New York
State
NY
Country
United States
Zip Code
10032
Hong, Sue; Washington, Patricia M; Kim, Ahleum et al. (2016) Apolipoprotein E Regulates Injury-Induced Activation of Hippocampal Neural Stem and Progenitor Cells. J Neurotrauma 33:362-74
Yu, Tzong-Shiue; Washington, Patricia M; Kernie, Steven G (2016) Injury-Induced Neurogenesis: Mechanisms and Relevance. Neuroscientist 22:61-71
Yousuf, Mohammad A; Tan, Chunfeng; Torres-Altoro, Melissa I et al. (2016) Involvement of aberrant cyclin-dependent kinase 5/p25 activity in experimental traumatic brain injury. J Neurochem 138:317-27
Kernie, Steven G (2015) Cell-based therapy for pediatric traumatic brain injury: not (yet) an update to the traumatic brain injury guidelines. Pediatr Crit Care Med 16:294-5
Yu, Tzong-Shiue; Kim, Ahleum; Kernie, Steven G (2015) Donepezil rescues spatial learning and memory deficits following traumatic brain injury independent of its effects on neurogenesis. PLoS One 10:e0118793