Estradiol signaling pathways mediating sex differences in striatal synaptic plasticity

物质使用障碍影响到约15%的人口，在物质使用的所有阶段都存在性别差异。 女性性类固醇荷尔蒙解释了一些差异，比如从临时使用加速到 成瘾，因为雌二醇会在啮齿动物的学习和可卡因自我管理中产生性别差异。 众所周知，长期使用可卡因会影响背侧纹状体回路。这种回路中的突触可塑性是至关重要的 对于各种类型的奖赏学习，强调这种可塑性在实质上可能起到的潜在作用 使用障碍。因此，了解可卡因使用中的性别差异需要确定雌二醇如何影响 背侧纹状体的分子信号与突触可塑性。我们的初步结果显示，雌二醇， 作用于雌二醇受体α，损害大鼠背内侧纹状体的长时程增强 发情的雌性；然而，雌激素作用的细胞类型尚未确定。纹状体棘突投射 神经元(SPN)既可以是促进活动的直接途径SPN，也可以是抑制活动的间接途径SPN 行动，这些SPN的变化对各种行为后果至关重要。因此，至关重要的是 了解直接和间接途径SPN中的LTP缺陷。在这个提案中，我们将检验这一假设 雌激素损伤DMS中间接途径SPN中的LTP。背侧纹状体中的LTP严重依赖于 细胞外调节激酶(ERK)的激活，它也被可卡因和雌二醇所修饰。 雌二醇促进可卡因介导的多巴胺释放并与代谢型谷氨酸受体相互作用 来改变ERK的激活，但需要一种公正的方法来确定雌二醇是否影响其他 信号通路。我们的初步结果已经确定了几个信号通路，它们被 然而，一个关键的问题是可卡因如何与雌二醇相互作用来调节这些信号。 小路。我们提出了前沿的分子和转基因方法，并结合了新的计算方法 建模以检验雌激素介导的基因表达变化损害LTP和TO的假设 确定可卡因如何进一步改变突触可塑性背后的信号通路。以特定的目标 1，我们在转基因小鼠身上进行电生理学，以确定LTP是否受到雌二醇的损害 两个SPN。在特定目标2中，我们使用了创新的单核RNA测序技术，翻译 核糖体亲和纯化、RNA测序和空间转录组学鉴定信号 雌激素和可卡因以特定细胞类型和空间方式自我给药改变的通路。在……里面 具体目标3，我们使用创新的、数据驱动的信号通路建模，然后是模型驱动 因果测试关键信号通路之间的相互作用产生雌二醇的实验 LTP中的赤字。这项拟议的研究的成功完成将勾勒出雌二醇如何影响突触 在背侧纹状体的可塑性，包括与可卡因的结合，并为今后的工作提供了基础 了解奖赏学习中的性别差异以及使用可卡因的后果。

Substance use disorders affect ~15% of the population, with gender differences in all stages of substance use. Female sex-steroid hormones explain some of the disparity, such as accelerated transition from casual use to addiction, as estradiol produces sex-specific differences in rodent learning and cocaine self-administration. Prolonged cocaine use is known to engage dorsal striatal circuits. Synaptic plasticity in such circuits is critical for a variety of types of reward learning, highlighting the potential role such plasticity could play in substance use disorders. Thus, understanding sex differences in cocaine use requires determining how estradiol impacts molecular signaling and synaptic plasticity in the dorsal striatum. Our preliminary results show that estradiol, acting at estradiol receptor type α, impairs long term potentiation (LTP) in dorsomedial striatum (DMS) in estrous females; however, the cell type in which estradiol acts has yet to be identified. Striatal spiny projection neurons (SPNs) are either direct pathway SPNs, which promote action, or indirect pathway SPNs, which inhibit action, and changes in these SPNs are critical for various behavioral consequences. Thus, it is essential to understand LTP deficits in both direct and indirect pathway SPNs. In this proposal, we will test the hypothesis that estradiol impairs LTP in indirect pathway SPNs in the DMS. LTP in the dorsal striatum critically depends on activation of extracellular regulated kinase (ERK), which also is modified by both cocaine and estradiol. Estradiol enhances cocaine-mediated dopamine release and interacts with metabotropic glutamate receptors to modify ERK activation, but an unbiased approach is needed to determine whether estradiol impacts other signaling pathways. Our preliminary results have identified several signaling pathways that are modified by estradiol; however, a critical question is how cocaine interacts with estradiol to modulate these signaling pathways. We propose cutting-edge molecular and transgenic approaches combined with novel computational modeling to test the hypothesis that estradiol-mediated changes in gene expression impair LTP and to determine how cocaine further modifies the signaling pathways underlying synaptic plasticity. In Specific Aim 1, we perform electrophysiology in transgenic mice to determine whether LTP is impaired by estradiol in one or both SPNs. In Specific Aim 2, we use innovative techniques of single nuclei RNA sequencing, translating ribosome affinity purification followed by RNA sequencing and spatial transcriptomics to identify signaling pathways modified by estradiol and cocaine self-administration in a cell-type specific and spatial manner. In Specific Aim 3, we use innovative, data-driven modeling of signaling pathways followed by model-driven experiments to causally test which interactions between critical signaling pathways produce estradiol-mediated deficits in LTP. Successful completion of the proposed research will delineate how estradiol influences synaptic plasticity in dorsal striatum, including in conjunction with cocaine, and provide a foundation for future work to understand sex differences in reward learning and the consequences of cocaine use.