Role of BDNF in Stress Effects on Ethanol Dependence-Induced Escalated Drinking

酒精使用障碍（AUD）是一种慢性复发性疾病，是退伍军人的主要健康问题。 众所周知，压力是酗酒和酒精中毒的一个重要因素，尤其是 与退伍军人相关，因为他们同时发生的AUD和压力相关疾病的患病率很高，例如 创伤性应激障碍（PTSD）。尽管这一问题的重要性， 压力和酒精（乙醇）饮酒还没有完全了解。动物模型的使用对于推进 我们对潜在机制的理解，并为评估潜在的新的和新颖的 对与PTSD-AUD合并症作斗争的退伍军人的治疗干预。最近的工作涉及我们建立的 涉及慢性间歇性乙醇（CIE）重复循环的乙醇依赖小鼠模型 暴露导致发现背内侧前额叶皮质（dmPFC）中BDNF活性的降低， 一种与过量饮酒有关的重要神经适应在当前的融资期内，我们 这项工作表明，压力促进和加强这种依赖性相关的乙醇升级 消费也就是说，强迫游泳应激（FSS）选择性地增强依赖性（CIE-1）饮酒的升级。 暴露）小鼠，而不改变非依赖性小鼠中更适度的乙醇摄入量。此外，在 与慢性乙醇暴露相结合，显示出放大了前额叶BDNF表达的缺陷， 皮层此外，我们证明了直接输注BDNF或病毒介导的BDNF过表达， dmPFC阻断依赖（CIE）相关的饮酒增加。总的来说，这些数据支持了 dmPFC中的脑源性神经营养因子活性降低在应激（FSS）增强的能力中发挥着重要作用 酗酒与依赖有关。众所周知，运动可以提高大脑中BDNF的活性， 进行的试点研究表明，运动减弱了依赖相关的酒精升级 饮酒，以及减弱压力的能力，以进一步提高过度饮酒相关的水平， 有依赖性。有了这些支持性的试验数据，拟议的研究计划将在这项工作的基础上建立和扩大 通过研究BDNF在运动减弱依赖性应激性饮酒能力中的作用， 小鼠具体来说，这项研究项目的目的是利用我们建立的压力-乙醇依赖（压力- CIE）饮酒模型，以检查运动是否减弱压力增强的依赖性相关过度 通过dmPFC中的BDNF-TrkB受体信号传导饮酒。拟议的研究将审查是否行使 （车轮运行）块应力（FSS）-增强逐步饮酒CIE暴露的小鼠，以及衰减 在Stress-CIE饮酒模型中伴随过度饮酒的dmPFC中BDNF表达减少 (Aim（一）。另一组研究将检查是否直接注射TrkB受体拮抗剂ANA-12到 dmPFC阻止车轮运行的能力，以衰减应力（FSS）-增强CIE引起的升级 饮酒以及通过siRNA输注敲低dmPFC中的TrkB受体是否产生类似的效果（Aim II）。最后，研究将检查是否用黄酮衍生物和TrkB受体进行全身治疗， 激动剂7，8-DHF替代运动，减轻压力增强CIE相关饮酒，和/或是否 在没有运动的情况下用7，8-DHF治疗模拟了在应激-CIE饮酒中运动的效果。 模型此外，研究将检查这些类似运动的行为效应是否是由于激活 在细胞中TrkB受体（pTrkB）和下游信号分子（pERK 1/2和pAKT）的磷酸化（磷酸化）。 dmPFC（目标III）。综上所述，这项建议涉及一项非常重要和临床重要的研究， 这是一个与退伍军人的健康护理密切相关的话题。该研究项目的成果将产生新的 关于潜在的新型治疗方法的机制的发现，该方法解决了临床相关的 健康问题-压力加剧的影响，导致有害的过量饮酒与 酗酒和PTSD-AUD合并症-对我们的退伍军人来说是一个特别重要的问题。

Alcohol use disorder (AUD) is a chronic relapsing disease that constitutes a major health problem for Veterans. Stress is known to be an important contributing factor to alcohol abuse and alcoholism, and this is especially relevant to Veterans given their high prevalence of co-occurring AUD and stress-related illnesses such as post- traumatic stress disorder (PTSD). Despite the significance of this problem, the complex interaction between stress and alcohol (ethanol) drinking is not fully understood. The use of animal models is critical for advancing our understanding of underlying mechanisms and providing platforms for evaluating potential new and novel treatment interventions for Veterans battling PTSD-AUD comorbidity. Recent work involving our established mouse model of ethanol dependence that involves repeated cycles of chronic intermittent ethanol (CIE) exposure led to the discovery that reduced BDNF activity in the dorsomedial prefrontal cortex (dmPFC) is a significant neuroadaptation associated with excessive drinking. During the current funding period, we extended this work to show that stress facilitates and enhances this dependence-related escalation of ethanol consumption. That is, forced swim stress (FSS) selectively enhances escalated drinking in dependent (CIE- exposed) mice while not altering more moderate ethanol intake in nondependent mice. Additionally, stress in combination with chronic ethanol exposure was shown to magnify deficits in BDNF expression in the prefrontal cortex. Further, we demonstrated that direct infusion of BDNF or viral-mediated overexpression of BDNF in the dmPFC blocked dependence (CIE)-related escalated drinking. Collectively, these data support the general tenet that reduced BDNF activity in the dmPFC plays a significant role in the ability of stress (FSS) to enhance escalated drinking associated with dependence. As exercise is known to elevate BDNF activity in brain, we conducted pilot studies that have demonstrated exercise attenuates dependence-related escalated ethanol drinking, as well as attenuating the ability of stress to further enhance excessive levels of drinking associated with dependence. With this supportive pilot data, the proposed research plan will build and expand on this work by examining the role of BDNF in the ability of exercise to attenuate stress-enhanced drinking in dependent mice. Specifically, this research project is aimed at utilizing our established stress-ethanol dependence (Stress- CIE) Drinking model to examine whether exercise attenuates stress-enhanced dependence-related excessive drinking via BDNF-TrkB receptor signaling in the dmPFC. Proposed studies will examine whether exercise (wheel-running) blocks stress (FSS)-enhanced escalated drinking in CIE-exposed mice, as well as attenuating reduced BDNF expression in dmPFC that accompanies excessive drinking in the Stress-CIE Drinking model (Aim I). Another set of studies will examine whether direct injection of the TrkB receptor antagonist ANA-12 into the dmPFC blocks the ability of wheel-running to attenuate stress (FSS)-enhanced CIE-induced escalated drinking and whether TrkB receptor knockdown in the dmPFC via siRNA infusion produces a similar effect (Aim II). Finally, studies will examine whether systemic treatment with the flavone derivative and TrkB receptor agonist 7,8-DHF substitutes for exercise in attenuating stress-enhanced CIE-related drinking, and/or whether treatment with 7,8-DHF in the absence of exercise mimics the effects of exercise in the Stress-CIE Drinking model. Additionally, studies will examine whether these exercise-like behavioral effects are due to activation (phosphorylation) of TrkB receptors (pTrkB) and downstream signaling molecules (pERK1/2 and pAKT) in the dmPFC (Aim III). Taken together, this proposal addresses a highly significant and clinically important research topic that is of great relevance to Veteran’s heath care. Results from this research project will generate new findings on mechanisms underlying a potential novel therapeutic approach that addresses a clinically relevant health problem - the exacerbating effects of stress that lead to harmful excessive drinking associated with alcoholism and PTSD-AUD comorbidity - an especially significant problem for our Veterans.