A Novel Pharmacotherapy for Alcoholism: Evaluation of Reward, Aversion, Compulsivity, Withdrawal & Reinstatement

项目摘要 酒精使用障碍给我们的社会带来了巨大的负担。除了他们的 心理和社会损失，据估计，AUDS每年给美国经济造成2490亿美元的损失 仅2010年一年。虽然已经有几种有效的行为和药物治疗方法， 迫切需要通过新机制发挥作用的新药物疗法。 我们最近发现，乙二酸酶1(GLO1)的抑制剂可以降低自愿性 小鼠饮用乙醇(McMurray等人，2007a)。GLO1是一种胞浆酶，可在体内代谢 甲基乙二醛(MG)。镁是糖酵解的一种非酶副产物，因此存在于 细胞。因此，GLO1活性与MG浓度呈负相关。我们之前已经表明， 转基因过表达GLO1可增加小鼠焦虑样行为并降低MG 大脑中的浓度。反过来，我们证明了直接给MG，Genetic 抑制Glo1或使用小分子抑制剂抑制GLO1均可降低焦虑样症状 并增加脑组织中MG的浓度。我们发现，更高剂量的MG会产生 运动性抑郁、共济失调和体温过低；综合这些数据，MG可能 通过GABA-A受体发挥作用。事实上，使用膜片钳程序，我们发现MG是一种 GABA-A受体的竞争性部分激动剂。我们还证明了MG是高度选择性的：它确实是 不激活GABA-B受体、其他配基门控离子通道或电压门控离子通道。更多 最近，我们发现GLO1抑制具有抗抑郁药样作用，提示GLO1 抑制剂可能会治疗焦虑和抑郁，这两种疾病都与AUD并存。给定 GABA-A信号在乙醇效应中的重要性，我们推测GLO1和MG可能 也调节与酒精相关的行为，这导致我们研究GLO1对酒精的影响 喝酒。这些研究表明，抑制GLO1可以减少饮酒，这是 本申请中提出的实验的基本原理。 我们正在提出一项研究，旨在了解为什么抑制GLO1会降低自愿 酒精饮酒。在目标1中，我们将使用颅内自我刺激(Icss)程序来检查 GLO1的遗传和药理作用对享乐性和慢性行为的急性和慢性影响 小鼠对酒精的非享乐性反应。在目标2中，我们将使用条件性位置偏好(CPP) 和条件性味觉厌恶(CTA)，以研究GLO1对 小鼠体内的乙醇。最后，在目标3中，我们将使用慢性间歇乙醇(CIE)程序来 检查Glo1抑制剂对急性酒精戒断、强迫症样反应的影响 酒精与大鼠长期戒断后寻酒行为的恢复。

Project Summary Alcohol use disorders (AUD) place an enormous burden on our society. In addition to their psychological and social toll, it is estimated that AUDs cost the US economy $249 billion in the year 2010 alone. Although there are already several effective behavioral and pharmacological treatments, there is an urgent need for new pharmacotherapies that act via novel mechanisms. We have recently shown that inhibitors of the enzyme Glyoxalase 1 (GLO1) reduce voluntary ethanol drinking in mice (McMurray, et al 2017a). GLO1 is a cytosolic enzyme that metabolizes methylglyoxal (MG). MG is a non-enzymatic side product of glycolysis and is therefore present in all cells. Thus, GLO1 activity is inversely related to MG concentration. We have previously shown that transgenic overexpression of GLO1 increases anxiety-like behavior in mice and decreases MG concentrations in the brain. Reciprocally, we showed that direct administration of MG, genetic knockdown of Glo1 or inhibition of GLO1 using a small molecule inhibitor all decrease anxiety-like behavior and increase MG concentrations in brain. We found that even higher doses of MG produced locomotor depression, ataxia and hypothermia; taken together these data suggested that MG might be acting through GABA-A receptors. Indeed, using a patch clamp procedure, we found that MG is a competitive partial agonist at GABA-A receptors. We also showed that MG is highly selective: it does not activate GABA-B receptors, other ligand gated ion channels or voltage gated ion channels. More recently, we have shown that GLO1 inhibition has antidepressant-like effects, suggesting that GLO1 inhibitors might treat anxiety and depression, both of which are comorbid with AUD. Given the importance of GABA-A signaling in the effects of ethanol, we speculated that GLO1 and MG might also modulate ethanol-related behaviors, which led us to study the effects of GLO1 on ethanol drinking. Those studies showed that inhibition of GLO1 decreased ethanol drinking, which is the rationale for the experiments proposed in this application. We are proposing studies aimed at understanding why inhibition of GLO1 reduces voluntary ethanol drinking. In Aim 1 we will use the intracranial self-stimulation (ICSS) procedure to examine the acute and chronic effects of genetic and pharmacological manipulations of GLO1 on hedonic and anhedonic responses to ethanol in mice. In Aim 2 we will use conditioned place preference (CPP) and conditioned taste aversion (CTA) to study the effects of GLO1 on preference and aversion for ethanol in mice. Finally, in Aim 3, we will use the chronic intermittent ethanol (CIE) procedure to examine the effects of Glo1 inhibitors on acute ethanol withdrawal, compulsive-like responding for ethanol and reinstatement of ethanol seeking behavior after protracted abstinence in rats.