Investigating Estrogen-Mediated Signaling in Binge Drinking Microcircuits of the Prefrontal Cortex

PROJECT SUMMARY/ABSTRACT Binge drinking among women presents a significant public health crisis, with both binge and heavy alcohol use among women surging over the past decade. Alcohol Use Disorder (AUD) is characterized by the presence of two or more clinical criteria indicating a sense of losing control over drinking habits. Estrogen (E2) levels are correlated with binge alcohol consumption levels across species, and repeated findings of menstrual cycle follicular/ovulatory phase and peak E2 promoting alcohol consumption are a strong argument for a mechanistic role in E2 for potentiating alcohol consumption in humans. Despite this, the mechanistic role of E2 in the sex differences in binge drinking behaviors driven by microcircuits of the prefrontal cortex (PFC) remains understudied. This fellowship proposes a comprehensive investigation into how E2 signaling influences binge drinking microcircuits of PFC somatostatin (SST) neurons in mice, through the following aims: Aim 1: Leveraging single molecule fluorescence in situ hybridization (RNAscope) and serum E2 measurements, transcriptional profiles of estrogen receptor α (ERα; Esr1) and β (ERβ; Esr2), Sst, and CaMKIIa in PFC neurons across the estrous cycle and following binge alcohol exposure will be assessed for their correlation with alcohol consumption with the voluntary Drinking in the Dark (DID) binge alcohol model. Aim 2: Whole-cell patch-clamp recordings of ex vivo SST-Ai9 brain slices will be assessed for changes in intrinsic excitability across estrous stages, and membrane potential with exogenous E2 after binge alcohol consumption. Furthermore, isotype specific estrogen receptor antagonists will be used to separate the contribution of ERα versus ERβ on changes in membrane potential with E2 bath application. Aim 3: Viral-mediated shRNA knockdown of ERα and ER expression specifically in PFC SST neurons will reveal the impact of ERα/ levels on binge alcohol consumption in female mice. This approach will allow direct assessment of the role of ERα/ in modulating alcohol consumption behavior. By integrating these approaches across transcriptional, electrophysiological, and behavioral levels of analysis, the proposed aims will provide a comprehensive understanding of how E2 signaling influences binge drinking microcircuits within the PFC. This research has significant implications for developing targeted interventions for alcohol use disorder, particularly in women, and underscores the importance of considering sex-specific hormonal influences in addiction research and treatment.