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，构成退伍军人的主要健康问题。 众所周知，压力是导致酗酒和酗酒的重要因素，尤其是 与退伍军人相关，因为他们合并AUD和与压力相关的疾病的患病率很高，如后 创伤应激障碍(PTSD)。尽管这个问题很重要，但两者之间的复杂相互作用 压力和酒精(酒精)饮酒还没有完全被理解。动物模型的使用对于推动 我们对潜在机制的理解，并为评估潜在的新事物提供平台 退伍军人抗击创伤后应激障碍-AUD共病的治疗干预。最近的工作涉及我们的老牌公司 反复慢性间歇性乙醇依赖的小鼠模型 暴露后发现，背内侧前额叶皮质(DmPFC)BDNF活性降低是 与过度饮酒相关的显著的神经适应。在本资金期限内，我们延长了 这项工作表明，压力促进并增强了乙醇依赖相关的这种升级 消费。也就是说，强迫游泳应激(FSS)选择性地增加依赖型(CIE- 暴露)小鼠，而不改变非依赖小鼠更多的适度乙醇摄入量。此外，压力在 慢性酒精暴露可放大前额叶脑源性神经营养因子的表达缺陷 大脑皮层。此外，我们还证明了直接注入BDNF或病毒介导的BDNF在 DmPFC阻止依赖(CIE)相关的饮酒升级。总体而言，这些数据支持总体原则 DmPFC中BDNF活性的降低在应激能力(FSS)增强中起着重要作用 与依赖相关的饮酒升级。众所周知，运动可以提高大脑中BDNF的活性，我们 进行了初步研究，证明运动可以减轻与依赖相关的酒精浓度上升 饮酒以及缓解压力的能力进一步增强了过度饮酒的相关水平 带着依赖。有了这些支持性的试点数据，拟议的研究计划将在这项工作的基础上建立和扩展 通过检测脑源性神经营养因子在运动能力中的作用来减轻依赖患者的应激性饮酒 老鼠。具体地说，这个研究项目的目的是利用我们已经建立的压力-酒精依赖(压力-酒精依赖)。 CIE)饮酒模型检验运动是否减轻压力增强的依赖相关的过度 饮酒通过dmPFC中的BDNF-TrkB受体信号传递。拟议的研究将检查锻炼是否 (跑轮)阻止压力(FSS)增加暴露于CIE的小鼠的饮酒增加，并减轻 在应激-CIE饮酒模型中，伴随过度饮酒的dmPFC中BDNF的表达减少 (目标I)。另一组研究将检查将TrkB受体拮抗剂ANA-12直接注射到脑内 DmPFC阻断了车轮转动对增强的CIE诱导的应力(FSS)的减弱作用 饮酒和是否通过siRNA注射敲除dmPFC中的TrkB受体会产生类似的效果(目的 Ii)。最后，研究将检查用黄酮衍生物和TrkB受体进行的全身治疗 激动剂7，8-DHF可替代运动减轻应激增强的CIE相关饮酒，和/或 在不运动的情况下使用7，8-DHF可模拟运动对应激性CIE饮酒的影响 模特。此外，研究还将检查这些类似锻炼的行为效应是否源于活动 TrkB受体(PTrkB)及其下游信号分子(pERK1/2和pakt)的磷酸化 DmPFC(AIM III)。综上所述，这项建议解决了一项具有高度意义和临床重要性的研究 与退伍军人医疗保健密切相关的话题。这一研究项目的成果将产生新的 一种潜在的新治疗方法的潜在机制的发现，该方法解决了临床相关的 健康问题-压力的恶化影响，导致有害的过量饮酒与 酒精中毒和创伤后应激障碍--这对退伍军人来说是一个特别严重的问题。

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.