Dissecting Brain Networks Underlying Alcohol Binge Drinking Using a Systems Genomics Approach

Area of Science:

• Neuroscience
• Genetics
• Molecular Biology

Background:

• Alcohol use disorder (AUD) is a complex psychiatric condition influenced by genetic and environmental factors.
• Understanding the molecular mechanisms of risky drinking behavior is crucial for developing effective treatments.

Purpose of the Study:

• To investigate the molecular perturbations underlying risky drinking behavior using a genetic mouse model.
• To analyze transcriptome changes across the neurocircuitry of addiction in selectively bred mice.

Main Methods:

• Utilized a genetic mouse model (High Drinking in the Dark - HDID-1) selectively bred for high alcohol consumption.
• Applied a systems approach integrating gene coexpression networks, neuron-specific transcriptional signatures, and knowledgebase analytics.
• Performed whole-cell, voltage-clamp recordings in nucleus accumbens neurons to assess ethanol-induced plasticity.

Main Results:

• Sixteen generations of selective breeding resulted in global changes in brain gene expression in alcohol-naïve HDID-1 mice.
• Differential ethanol-induced plasticity was observed in nucleus accumbens shell neurons projecting to the ventral tegmental area.
• Gene networks in HDID-1 mouse brains showed similarities to postmortem brains of human alcoholics, indicating conserved patterns.

Conclusions:

• Gene expression patterns associated with high alcohol consumption are conserved across species.
• Gene networks are valuable for integrating data across modalities and species to study AUD mechanisms.
• This study provides insights into the molecular basis of addiction and potential therapeutic targets.