The overall goal of this proposal is to determine the importance of adult hippocampal neurogenesis to the recovery process following extended access methamphetamine intake. Research into understanding the neurobiological basis of addiction and relapse has significantly progressed, but to date few treatments are known to reverse the drug-induced neuroplasticity changes that convey vulnerability to relapse. Understanding the neuroplastic changes that underlie the relapse stage of addiction can help generate better treatment options for addiction. One potential mechanism to accelerate brain repair during withdrawal is stimulating the generation of neurons from adult neural stem cells - a process known as adult hippocampal neurogenesis. Neural stem cells persist in the adult hippocampal subgranular zone (SGZ). Adult hippocampal neurogenesis is involved in some aspects of methamphetamine addiction, as reinforcing doses of methamphetamine reduce proliferation, differentiation and neurogenesis of neural stem cells in the SGZ. However, the effects of withdrawal from methamphetamine on these stages of hippocampal neurogenesis are unknown. Furthermore, it is unclear if the process of adult neurogenesis can be stimulated during withdrawal;the types of neurons that can be replaced during withdrawal and their ability to integrate into preexisting circuitry. In the proposed studies, innovative genetic, electrophysiological and immunohistochemical techniques and behavioral models will be used to specifically label, stimulate or inhibit adult-generated neurons in the setting of extended access methamphetamine intake. Using these approaches, we will test our central hypothesis that hippocampal neurogenesis contributes to repair after withdrawal from extended access methamphetamine via neuronal replacement;thus, inhibiting this process will impair recovery and stimulating this process will augment recovery and reduce or prevent relapse. Studies in Aim 1 will characterize the long-term survival and integration of adult-generated neurons after methamphetamine self-administration. Experiments in Aim 2 will determine if adult neurogenesis is critical to the prevention of relapse.
In Aim 3, we will determine whether adult neurogenesis during withdrawal contributes to functional recovery and prevents relapse.

Public Health Relevance

Neural stem cells persist in the hippocampus in the adult mammalian brain. The proposed studies seek to determine whether hippocampal neural stem cells play a role in reducing relapse, assist with repair by replacing cells damaged by brain disorders and promote recovery.

Agency
National Institute of Health (NIH)
Institute
National Institute on Drug Abuse (NIDA)
Type
Research Project (R01)
Project #
5R01DA034140-02
Application #
8686809
Study Section
Neurobiology of Motivated Behavior Study Section (NMB)
Program Officer
Pilotte, Nancy S
Project Start
2013-07-01
Project End
2018-03-31
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
2
Fiscal Year
2014
Total Cost
$298,463
Indirect Cost
$140,963
Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
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