Benzodiazepine treatment induced neuroplasticity

苯二氮卓类(BZS)是广泛用于治疗焦虑、失眠和癫痫的治疗药物， 作为精神分裂症和抑郁症的额外药物治疗。补肾益气汤结合并增强血管紧张素转换酶抑制活性 GABA A型受体的特定亚型(GABAARs)。尽管BZS有效，但它们的长期使用是 受到容忍、依赖和退缩的严重限制。从机制上讲，人们对此知之甚少 神经适应是BZ耐受性大脑状态的基础。慢性BZ治疗导致BZ减少 GABA受体活性增强，提示受体亚单位组成和/或功能发生变化 抑制性突触。此外，在BZ治疗期间发生的神经可塑性也依赖于 兴奋性谷氨酸能N-甲基-D-天冬氨酸受体(NMDAR) 拮抗剂可以防止BZ耐受。使用高通量定量蛋白质组学方法 我们的数据首次显示，研究BZ镇静耐受诱导的啮齿动物皮质变化 关键的兴奋性突触成分显著上调。加上我们之前的工作表明 持续暴露BZ会降低BZ敏感GABA受体的突触水平，这些发现产生了 中心假设：苯二氮类药物治疗减少苯并敏感的GABAAR亚型信号转导 伴随着兴奋性突触强度的增强。这项拟议的研究充分利用了 新的光学方法和定量蛋白质组学解决BZ延长的关键知识缺口 USE在抑制性GABAAR和兴奋性NMDAR信号中均可诱导神经可塑性。两个独立的和 提出了互补的目标来检验BZ耐受性的这些机械成分。第一个目标是 使用定量质谱学、电生理学、行为学和药理学方法来定义和 体内BZ治疗引起的抑制性和兴奋性突触变化的功能评价 啮齿动物皮质。第二个目标将应用高分辨率成像技术和创新的光学技术 BZ敏感的体内外生物传感器，结合遗传、生化和生物化学 电生理学方法识别BZ处理引起的GABAAR翻译后修饰和 导致BZ快速解偶联和进展为BZ镇静耐受的细胞机制。这些 研究结果将为开发减轻或避免BZ的治疗方法提供新的方向 宽容，解决一个重大的未得到满足的公共卫生需求。

Benzodiazepines (BZs) are therapeutic drugs widely used to treat anxiety, insomnia and seizure disorders and as additional drug therapy in schizophrenia and depression. BZs bind and potentiate the inhibitory activity of specific subtypes of GABA type A receptors (GABAARs). Despite the efficacy of BZs, their prolonged use is severely limited by tolerance, dependence and withdrawal. Very little is mechanistically known about the neuroadaptations that underlie a BZ tolerant brain state. Chronic BZ treatment results in a decrease in BZ potentiation of GABA activity at GABAARs, suggesting changes in receptor subunit composition and/or function at inhibitory synapses. Furthermore, the neuroplasticity occurring during BZ treatment is also dependent on excitatory glutamatergic N-methyl-D-aspartate receptors (NMDAR), as co-administration of NMDAR antagonists can prevent BZ tolerance. Using a high throughput quantitative proteomic approach to investigate BZ sedative tolerance-induced changes in the rodent cortex our data show for the first time significant upregulation of key excitatory synapse components. Together with our prior work showing that sustained BZ exposure decreases synaptic levels of BZ sensitive GABAARs, these findings generated the central hypothesis: Benzodiazepine treatment reduces benzo-sensitive GABAAR subtype signaling concomitant with enhancing excitatory synapse strength. The proposed research capitalizes on the use of novel optical methods and quantitative proteomics to address the critical knowledge gap in how prolonged BZ use induces neuroplasticity in both inhibitory GABAAR and excitatory NMDAR signaling. Two independent and complementary Aims are proposed to test these mechanistic components of BZ tolerance. The first aim will use quantitative mass spectrometry, electrophysiology, behavioral and pharmacological methods to define and functionally assess in vivo BZ treatment induced changes in both inhibitory and excitatory synapses of the rodent cortex. The second aim will apply high resolution imaging techniques and an innovative optical biosensor for BZ sensitive GABAAR in vitro and in vivo, combined with genetic, biochemical and electrophysiological approaches to identify BZ treatment induced GABAAR post translational modifications and cellular mechanisms leading to rapid BZ uncoupling and the progression to BZ sedative tolerance. These findings will provide new directions for the development of therapeutic approaches to mitigate or avoid BZ tolerance, addressing a significant unmet public health need.