T-Channel Dysregulation during Alcohol Withdrawal: Mechanisms and Novel Therapies

描述(申请人提供)：本研究培训计划的主要目标是确定酒精戒断过程中T-型钙通道(T-通道)调节失调的分子机制，并确定T-通道是否可以作为酒精戒断发作的临床前治疗靶点。包括癫痫发作在内的戒断症状会促使个人复发，因此是康复的重大障碍。随着每一次连续的戒断，症状的严重性会增加，出现一种类似点燃的现象。由于酒精对中枢神经系统的抑制作用，继而产生递进性神经元兴奋的代偿机制，同时伴随着紊乱的大脑节律的发展。使用间歇性酒精暴露范式，我们的实验室已经发现在戒断过程中丘脑T型钙异构体CaV3.2的中断，这可能是戒断发作产生和传播的基础。T-通道兴奋性异常升高的机制以及针对T-通道的药物治疗是否有效，目前尚不清楚。我建议在多个层面上解决这一潜在的机制。具体目标1将评估非特异性T通道拮抗剂乙硫胺的使用，以及CaV3.2特异性T通道拮抗剂抗坏血酸的使用，以对抗酒精戒断时的癫痫活性。为了进一步揭示酒精戒断过程中T通道失调的机制，AIMS 2和3将评估翻译后修饰是否通过蛋白激酶C(PKC)介导所观察到的兴奋性增加，以及神经元限制性沉默因子(NRSF)在转录调控中的作用。 CaV3.2 T形通道。这项拟议的培训计划涉及一种多学科方法，将有助于通过更好地了解机制和确定新的治疗干预目标来促进酒精领域的发展。这种研究方法将提供电生理学和分子技术方面的培训，包括外科手术、脑电分析、膜片钳电生理学、定量逆转录聚合酶链式反应(qRT-PCR)和Western印迹技术。在顾问和研究助理的指导和支持下，该项目将提供必要的培训，以追寻问题，从而深入了解长期酗酒后出现的严重情况。 与公共卫生相关：酒精戒断症状，包括癫痫发作，会促使个人复发，并对康复构成重大障碍。确定负责任的机制和新的治疗目标对于帮助个人从酗酒中恢复至关重要，并将降低经济负担和死亡率。研究酒精戒断过程中T通道的失调不仅有助于我们了解过度兴奋的机制，而且可能是未来药物干预的一种有前途的策略。

DESCRIPTION (provided by applicant): The primary objectives of this research training plan is to identify the molecular mechanisms responsible for T- type calcium channel (T-channel) dysregulation during alcohol withdrawal, and to determine whether T- channels can serve as preclinical therapeutic targets for alcohol withdrawal seizures. Withdrawal symptoms including seizures drive individuals to relapse, thus representing a significant barrier to recovery. With each successive withdrawal, symptoms increase in severity in a kindling-like phenomenon. Due to the depressing effects of alcohol in the CNS, compensatory mechanisms of progressive neuronal excitation ensue, with concurrent development of disrupted brain rhythms. Using an intermittent alcohol exposure paradigm, our lab has identified a disruption in the thalamic T-type calcium isoform, CaV3.2, during withdrawal that may underlie the generation and propagation of withdrawal seizures. The mechanisms responsible for the abnormal increases in excitability of T-channels are unknown, as well as whether or not pharmacological treatments targeting T-channels may be effective. I propose to address this potential mechanism at multiple levels. Specific Aim 1 will evaluate the use of ethosuximide, a non-specific T-channel antagonist, and the use of ascorbate, a specific CaV3.2 T-channel antagonist, as treatments against seizure acitivity during alcohol withdrawal. To further reveal mechanisms responsible for T-channel dysregulation during alcohol withdrawal, Aims 2 and 3 will evaluate if posttranslational modifications mediate the observed increase in excitability via protein kinase C (PKC) and the role of neuron-restrictive silencer factor (NRSF) in transcriptional regulation of CaV3.2 T-channel. This training plan proposed involves a multidisciplinary approach that will serve to advance the alcohol field by providing a better understanding of mechanisms and identifying novel targets for therapeutic intervention for individuals suffering from alcohol abus. This research approach will provide training in both electrophysiology and molecular techniques including surgical procedures, EEG analysis, patch clamp electrophysiology, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and Western blot techniques. With guidance and support from the advisor and research associates, this project will provide the necessary training to pursue questions that will provide insight into the serious conditions that develop after chronic alcohol abuse. PUBLIC HEALTH RELEVANCE: Alcohol withdrawal symptoms, including seizures, drive individuals to relapse and represent a significant barrier to recovery. Indentifying mechanisms responsible and novel therapeutic targets is critical to help individuals recovering from alcohol abuse and will lower the economic burden and fatality rates. Investigating T-channel dysregulation during alcohol withdrawal will not only help us understand mechanisms for increased hyperexcitability but may be a promising strategy for future pharmacological interventions.