Microglia,-the resident macrophages of the central nervous system (CNS), are thought to be important contributors to CNS health and' disease but their exact functional roles are still mysterious. Direct CNS damage, as well as peripheral injuries and addictive drug exposure, all induce microglial activation. A longstanding limitation in investigating microglia is the lack of good tools to distinguish and manipulate microglia specifically without altering macrophages or other immune cell types. In this proposal we will use new tools that our lab has recently generated to specifically identify and genetically manipulate microglia in order to investigate their function. First we will use these tools to develop the first in vitro culture system in which purified microglial cells can be cultured in defined serum-free medium with high survival in a non- activated state. This will enable us to directly test their specific functions for the first time including their ability to promote neuronal and glial survival, or to regulate synapse formation and function, as well as to elucidate the specific signals that induce their activation and to assess how their normal functions are altered when microglia become activated. Second, we will perform metabolomics analysis to investigate nature of the chemical signaling molecules that resting and activated microglial cells secrete. Third, we will use the new genetic tools we have developed to ablate microglia to elucidate their role in the establishment and maintenance of reactive gliosis and neuropathic pain. Lastly vye will identify the specific molecular mechanisms through which microglial cells influence these processes. Presently, drugs available for treatment of pain, such as opiates, suffer from undesired side effects and the development of tolerance. The purpose of the proposed research is to determine the molecular events that produce glial cell mediated neural circuitry modifications, opioid tolerance and addiction, as well as neuropathic pain in order to identify novel therapeutic targets. The findings will lay the groundwork for future research in understanding the role of microglia in drug- induced plasticity in reward-related neuronal circuits.

Agency
National Institute of Health (NIH)
Institute
National Institute on Drug Abuse (NIDA)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37DA015043-17
Application #
9220766
Study Section
Special Emphasis Panel (NSS)
Program Officer
Sorensen, Roger
Project Start
2001-07-15
Project End
2019-01-31
Budget Start
2017-02-01
Budget End
2018-01-31
Support Year
17
Fiscal Year
2017
Total Cost
$362,141
Indirect Cost
$137,141
Name
Stanford University
Department
Neurology
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94304
Bennett, F Chris; Bennett, Mariko L; Yaqoob, Fazeela et al. (2018) A Combination of Ontogeny and CNS Environment Establishes Microglial Identity. Neuron 98:1170-1183.e8
Bohlen, Christopher J; Bennett, F Chris; Tucker, Andrew F et al. (2017) Diverse Requirements for Microglial Survival, Specification, and Function Revealed by Defined-Medium Cultures. Neuron 94:759-773.e8
Liddelow, Shane A; Guttenplan, Kevin A; Clarke, Laura E et al. (2017) Neurotoxic reactive astrocytes are induced by activated microglia. Nature 541:481-487
Corder, Gregory; Tawfik, Vivianne L; Wang, Dong et al. (2017) Loss of ? opioid receptor signaling in nociceptors, but not microglia, abrogates morphine tolerance without disrupting analgesia. Nat Med 23:164-173
Bennett, Mariko L; Bennett, F Chris; Liddelow, Shane A et al. (2016) New tools for studying microglia in the mouse and human CNS. Proc Natl Acad Sci U S A 113:E1738-46
Jin, Xiaoming; Jiang, Kewen; Prince, David A (2014) Excitatory and inhibitory synaptic connectivity to layer V fast-spiking interneurons in the freeze lesion model of cortical microgyria. J Neurophysiol 112:1703-13
Kim, Doo-Sik; Li, Kang-Wu; Boroujerdi, Amin et al. (2012) Thrombospondin-4 contributes to spinal sensitization and neuropathic pain states. J Neurosci 32:8977-87
Blank, Martina; Fuerst, Peter G; Stevens, Beth et al. (2011) The Down syndrome critical region regulates retinogeniculate refinement. J Neurosci 31:5764-76
Jin, Xiaoming; Huguenard, John R; Prince, David A (2011) Reorganization of inhibitory synaptic circuits in rodent chronically injured epileptogenic neocortex. Cereb Cortex 21:1094-104
Cheng, Ting-Wen; Liu, Xiao-Bo; Faulkner, Regina L et al. (2010) Emergence of lamina-specific retinal ganglion cell connectivity by axon arbor retraction and synapse elimination. J Neurosci 30:16376-82

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