Document text
Principal Investigator: Rong Chen
Organization: WAKE FOREST UNIVERSITY HEALTH SCIENCES
Fiscal Year: 2024
Award: $558,617
Funding agency: National Institute on Alcohol Abuse and Alcoholism
Project Summary
Current NIAAA strategic plan calls for efforts to identify novel molecular actions of alcohol and new remedies to
mitigate alcohol-impacted brain regions. Ever-changing research tools have exponentially accelerated our
understanding of brain regions and circuits affected by alcohol use and comorbid affective disorders. However,
efforts towards the understanding of molecular mechanisms for altered neural activity in these impacted
regions have lagged behind. To fill in this gap, we will explore a previously unknown molecular mechanism
whereby ethanol modulation of brain cholesterol in the prefrontal cortex (PFC) leads to aberrant mGluR2
function and glutamate transmission in a rodent model of chronic intermittent ethanol (CIE) exposure. This
modulation may thus contribute to alcohol drinking and anxiety-like behavior, commonly observed in patients
with alcohol use disorder (AUD). Using a CIE rodent model, we show that CIE increases glutamate release in
the PFC along with increased alcohol drinking and anxiety-like behavior. Further, we and others report that
ablation of PFC neuron projection to subcortical regions (e.g. BLA or NAc) abolishes these behaviors. Thus,
the PFC is a critical hub for regulating dependence-related neural and behavioral activity. However, the
molecular mechanisms underlying CIE-induced disruption of glutamate transmission in the PFC remain
elusive. Our preliminary data strongly suggest mGluR2 involvement in this region: a) CIE spatially segregates
mGluR2 from Gαo subunit and reduces mGluR2 stimulation of Gαi/o; b) CIE abolishes mGluR2 inhibition of
Gβγ-mediated presynaptic glutamate release and postsynaptic intrinsic excitability of PFC neurons; and c) CIE
impairs mGluR2 inhibition of anxiety-like behavior. Such a deficit in mGluR2 function may be governed by
membrane cholesterol. We found that CIE drastically increases cholesterol content in the PFC by enhancing
the activity of HMG-CoA-reductase (HMGCR), a cholesterol synthesis enzyme. Importantly, reduced, CIE-
dependent mGluR2 function can be reversed by ex vivo cholesterol removal and mimicked by ex vivo
cholesterol addition to naïve tissue. We hypothesize that blockade of cholesterol increase will attenuate CIE-
dependent disruption of mGluR2-mediated G-protein activation, neurophysiology and dependence-related
behaviors. We will use CRISPR/Cas9, cellular, electrophysiological and behavioral approaches to test our
hypothesis. The proposal is conceptually and technically innovative and significant, investigating a largely
overlooked and potentially impactful effect of CIE exposure on cholesterol modulation of mGluR2 function,
glutamate transmission and anxiety-like behavior.
Terms: <3-hydroxy-3-methylglutaryl-CoA><3-hydroxy-3-methylglutaryl-coenzyme A><Ablation><Abscission><Absolute ethanol><Acceleration><Affect><Affective Disorders><Alcohol Chemical Class><Alcohol Drinking><Alcohol consumption><Alcohols><Animals><Attenuated><Behavior><Behavioral><Binding><Body Tissues><Brain><Brain Nervous System><Brain region><CRISPR approach><CRISPR based approach><CRISPR method><CRISPR methodology><CRISPR technique><CRISPR technology><CRISPR tools><CRISPR-CAS-9><CRISPR-based method><CRISPR-based technique><CRISPR-based technology><CRISPR-based tool><CRISPR/CAS approach><CRISPR/Cas method><CRISPR/Cas technology><CRISPR/Cas9><CRISPR/Cas9 technology><Cas nuclease technology><Cell Communication and Signaling><Cell Signaling><Cholesterol><Cholesterol Homeostasis><Chronic><Clustered Regularly Interspaced Short Palindromic Repeats approach><Clustered Regularly Interspaced Short Palindromic Repeats method><Clustered Regularly Interspaced Short Palindromic Repeats methodology><Clustered Regularly Interspaced Short Palindromic Repeats technique><Clustered Regularly Interspaced Short Palindromic Repeats technology><Common Rat Strains><Data><Dehydrogenases><Density Gradient Centrifugation><Density Gradient Fractionation><Dependence><ETOH><Electrophysiology><Electrophysiology (science)><Encephalon><Enzyme Gene><Enzymes><EtOH drinking><EtOH use><Ethanol><Ethanol dependence><Ethyl Alcohol><Excision><Extirpation><G-Proteins><GTP-Binding Proteins><GTP-Regulatory Proteins><Genes><Glutamates><Grain Alcohol><Guanine Nucleotide Coupling Protein><Guanine Nucleotide Regulatory Proteins><HMG-CoA><Impairment><Intracellular Communication and Signaling><Knowledge><L-Glutamate><Learning><Lentiviral Vector><Lentivirus Vector><Measures><Mediating><Membrane><Methylcarbinol><Microdialysis><Molecular><Molecular Interaction><Molecular Target><Monitor><Mood Disorders><NIAAA><National Institute on Alcohol Abuse and Alcoholism><Nerve Cells><Nerve Impulse Transmission><Nerve Transmission><Nerve Unit><Neural Cell><Neurobiology><Neurocyte><Neuronal Transmission><Neurons><Neurophysiology / Electrophysiology><Oxidoreductase><Oxidoreductase Gene><Patients><Prefrontal Cortex><Rat><Rats Mammals><Rattus><Reductases><Removal><Reporting><Research><Rodent Model><Saccharose><Signal Transduction><Signal Transduction Systems><Signaling><Strategic Planning><Sucrose><Surgical Removal><Synapses><Synaptic><Testing><Therapeutic Intervention><Tissues><Transmission><alcohol abuse therapy><alcohol abuse treatment><alcohol behavior><alcohol co-morbidity><alcohol comorbidity><alcohol exposed><alcohol exposure><alcohol induced behavior><alcohol ingestion><alcohol intake><alcohol product use><alcohol related behavior><alcohol treatment><alcohol use><alcohol use disorder><alcoholic beverage consumption><alcoholic drink intake><anxiety-like behavior><attenuate><attenuates><axon signaling><axon-glial signaling><axonal signaling><behavior measurement><behavioral measure><behavioral measurement><biological signal transduction><cholesterol metabolism><density gradient ultracentrifugation><electrophysiological><ethanol addiction><ethanol behavior><ethanol consumption><ethanol dependency><ethanol dependent><ethanol drinking><ethanol exposed><ethanol exposure><ethanol induced behavior><ethanol ingestion><ethanol intake><ethanol product use><ethanol related behavior><ethanol use><ethanol use disorder><exposed to alcohol><exposed to ethanol><exposure to alcohol><exposure to ethanol><extracellular><glia signaling><glial signaling><glutamatergic><hydroxymethylglutaryl-CoA><improved><innovate><innovation><innovative><intervention therapy><mGluR2><membrane structure><metabotropic glutamate receptor 2><nerve signaling><neural><neural signaling><neurobiological><neuronal><neuronal excitability><neuronal signaling><neurophysiological><neurophysiology><neurotransmission><novel><postsynaptic><presynaptic><prevent><preventing><protein activation><resection><segregation><synapse><tool><transmission process>