Role of ABHD6 in 2-AG Signaling

描述(申请人提供)：针对大脑中的内源性大麻素(ECB)信号的化合物是探索该信号系统在健康和疾病大脑中的基本生物学功能的强大药理学工具，并可能代表治疗亨廷顿病(HD)等神经疾病的新治疗场所。在RO1的资助周期中，我们的实验室研究了ABHD6在神经元和神经胶质细胞中的功能，以及ABHD6抑制剂在R6/2小鼠(一种早发性HD小鼠模型)上的治疗潜力。我们利用功能蛋白质组学和shRNA技术，确定ABHD6是脑内2-AG水解酶的候选酶。然后我们开发了新的ABHD6抑制剂，并表明ABHD6的活性严格控制了2-AG在大麻素受体上的水平和疗效。这些研究表明，ABHD6属于欧洲央行的信号系统。最近我们发现，在体内，ABHD6抑制大大降低了R6/2小鼠癫痫的发生率，并减轻了海马神经病理改变。在这项资助中，我们将检验以下假设：新型酶ABHD6控制大麻素CB1受体上2-花生四烯基甘油(2-AG)的水平和有效性。ABHD6抑制剂降低了两种HD小鼠模型(R6/2和HDQ200)的癫痫发作活性，可能代表了一类治疗癫痫的新疗法。为了验证这一假说，我们提出了三个目标：目标1：具有良好体内选择性和有效性的第三代ABHD6抑制剂的开发、验证和作用机制。目的2：确定ABHD6体内抑制和基因缺失在多大程度上降低HD和化学诱导癫痫小鼠模型的癫痫发生率。目标3：为什么HD小鼠会癫痫发作，ABHD6是如何阻止这一过程的？因此，我们将对新优化的ABHD6抑制剂进行表征，ABHD6是我们在前一个资金时期确定的一种欧洲央行水解酶。结合遗传方法，我们将使用ABHD6抑制剂来确定这种酶如何控制HD小鼠模型中癫痫发作的分子和细胞细节。上述研究的完成将提供对ABHD6在癫痫活动背景下健康和HD小鼠大脑中的作用的全面了解。我们的长期目标是增加我们对ABHD6在健康和患病大脑中所起作用的了解，并帮助开发新的疗法，避免经典大麻类激动剂产生的滥用和不良反应的可能性。

DESCRIPTION (provided by applicant): Compounds that target endocannabinoid (eCB) signaling in the brain represent powerful pharmacological tools to probe the basic biological function of this signaling system in healthy and diseased brain and may represent novel therapeutic venues to treat neurological diseases such as Huntington's disease (HD). During the funding cycle of this RO1, our laboratory studied the function of ABHD6 in neurons and glia, as well as the therapeutic potential of ABHD6 inhibitors in R6/2 mice, an early-onset mouse model of HD. We leveraged functional proteomics and shRNA technology and identified ABHD6 as a candidate enzyme for 2-AG hydrolysis in brain. We then developed new ABHD6 inhibitors and showed that ABHD6 activity tightly controls the levels and efficacy of 2-AG at cannabinoid receptors. Together, these studies demonstrated that ABHD6 belongs to the eCB signaling system. Recently we found that in vivo ABHD6 inhibition greatly reduces seizure incidence and attenuates hippocampal neuropathology in R6/2 mice. In this grant, we will test the following hypothesis: The novel enzyme, ABHD6, controls both the level and efficacy of 2-arachidonoylglycerol (2-AG) at cannabinoid CB1 receptors. ABHD6 inhibitors reduce seizure activity in two HD mouse models (R6/2 and HDQ200) and may represent a novel class of therapeutics to treat seizures in general. To test this hypothesis, we propose 3 Aims: AIM 1: Development, validation, and mechanism of action of 3rd generation ABHD6 inhibitors that exhibit superior in vivo selectivity and efficacy. AIM 2: Determine to what extent ABHD6 in vivo inhibition and genetic deletion reduces seizure incidence in HD and chemically-induced seizures mouse models. AIM 3: Why do HD mice seize, and how does ABHD6 prevent this process? Thus we will characterize newly optimized inhibitors of ABHD6, an eCB-hydrolyzing enzyme that we identified during the previous funding period. Coupled to genetic approaches, we will use ABHD6 inhibitors to determine the molecular and cellular details of how this enzyme controls seizure incidence in HD mice models. Completion of the studies outlined above will provide a comprehensive understanding of the role of ABHD6 in healthy and HD mouse brain within the context of epileptic activity. Our long-term goal is to increase our understanding of th role played by ABHD6 in healthy and diseased brain, and help develop novel therapeutics that lack the potential for abuse and adverse effects produced by classic cannabinoid agonists.