Biochemical Studies Underlying Acute Ethanol's Antidepressant-like effects during Withdrawal in a Preclinical Model of Ethanol Dependence

项目概要 重度抑郁症（MDD）和酒精使用障碍（AUD）是共病的。急性酒精会降低两者 焦虑和抑郁样行为。长期接触酒精会增加这两种负面情绪—— 喜欢的行为。事实上，数十年的流行病学数据表明，个人使用酒精来缓解 消极的情感状态。负面情绪状态是否是由于重度抑郁症或反复酗酒造成的 （澳元），研究人员现在开始研究最初积极且有益的机制如何 戒断期间转向负面情绪/快感缺乏。例如，我们对神经网络了解很多。 酒精对焦虑样急性和慢性影响的电路和神经递质/肽系统 行为。令人惊讶的是，人们对负面情感（快感缺乏）的关注要少得多。 组件。我们的临床前工作表明，急性乙醇治疗会产生类似抗抑郁的作用 并劫持与 NMDAR 拮抗剂相同的生化途径。对乙醇和 NMDAR 至关重要 拮抗剂的抗抑郁功效取决于 RNA 结合蛋白 Fragile X Mental 的动态表达 延迟蛋白（FMRP）。 FMRP 表达的减少允许跨突触的上调 促进新突触形成和抗抑郁样作用的蛋白质。与从 的转变一致 FMRP 在乙醇依赖性戒断期间上调，从积极到消极的情绪样行为 动物。利用分子、生物化学和电生理学技术，结合新型突触 我们在实验室开发的检测方法 (DetectSyn) 以及我们合作者在该领域的专业知识 Weiner 实验室在酒精依赖的临床前模型中，我们将在特定目标 1 中确定是否急性 乙醇调节 FMRP 与突触 mRNA 的结合，调节突触蛋白的合成 这些目标 mRNA，并促进新突触的形成。此外，在具体目标 2 中，我们将确定是否 FMRP 调节的抗抑郁信号通路在 WD/负面情绪期间被减弱或抑制 状态，以及急性乙醇治疗是否可以逆转生化和行为抑郁表型。 此外，我们将分离并测序 FMRP 靶标 mRNA，这些 mRNA 在 WD 期间被抑制但被释放 由于 WD 期间使用急性乙醇治疗。使用计算/基因组方法，例如图书馆 基于集成网络的蜂窝签名——一种在 AUD 研究中显示出前景的方法——这些 数据将有助于未来的研究使用这些目标来预测 FDA 批准的有效的、重新利用的药物 治疗 AUD 和 MDD。这些研究将为未来药物干预治疗奠定基础 对于患有 MDD 的酒精依赖者来说，WD 期间会产生负面影响。

PROJECT SUMMARY Major depressive disorder (MDD) and alcohol use disorder (AUD) are comorbid. Acute alcohol decreases both anxiety- and depressive-like behaviors. Chronic alcohol exposure increases both of these negative emotion- like behaviors. In fact, decades of epidemiological data suggest that individuals use alcohol to alleviate a negative affective state. Whether the negative emotional state is due to MDD or repeated alcohol exposure (AUD), researchers are now beginning to examine how mechanisms that are initially positive and rewarding shift toward negative affect/anhedonia during withdrawal. For example, much is known about the neural circuitry and neurotransmitter/peptide systems underlying acute and chronic effects of alcohol on anxiety-like behaviors. Surprisingly, much less attention has been directed at the negative affective (anhedonia) component. Our preclinical work suggests that acute ethanol treatment produces an antidepressant-like effect and hijacks the same biochemical pathway as NMDAR antagonists. Pivotal to ethanol and NMDAR antagonists’ antidepressant efficacy is the dynamic expression of the RNA-binding protein Fragile X Mental Retardation Protein (FMRP). Reduction in FMRP expression allows for the upregulation of transsynaptic proteins that promote new synapse formation and antidepressant-like effects. Consistent with a shift from positive to negative emotion-like behaviors, FMRP is upregulated during withdrawal in ethanol-dependent animals. Using molecular, biochemical, and electrophysiological techniques, combined with a novel synapse detection assay that we developed in our laboratory (DetectSyn), and the expertise of our collaborators in the Weiner laboratory in preclinical models of alcohol dependence, we will determine in Specific Aim 1 if acute ethanol regulates the binding of FMRP to transsynaptic mRNAs, regulates the synaptic protein synthesis of these target mRNAs, and promotes new synapse formation. Moreover, in Specific Aim 2 we will determine if the FMRP-regulated antidepressant signaling pathway is muted or suppressed during the WD/negative affect state, and if acute ethanol treatment can reverse the biochemical and behavioral depressive phenotypes. Furthermore, we will isolate and sequence FMRP target mRNAs that are repressed during WD but released due to treatment with acute ethanol during WD. Using a computational/genomic approach such as the Library of Integrated Network-Based Cellular Signatures – a method that has shown promise in AUD research – these data will facilitate future studies using these targets to predict effective, repurposed FDA-approved drugs to treat AUD and MDD. These studies will lay the foundation for future pharmacological intervention to treat negative affect during WD in alcohol-dependent individuals with comorbid MDD.